Just for the sake of correctness...
Only the Vasari SB has 3 available upgrades to weapons (although the third doesn't add any new weapons - its the 20% damage increase)
The Advent SB gets lasers on its first upgrade, Psionic Surge on the second. So, the Advent do get a (relatively speaking) favourable weapon on its first upgrade, unfavourable on the second.

I suspect that the AM cost of Repair Bots is low in comparison to the max AM for a Hoshi (something like 7-9 casts, AM regen and abilities ignored), so unless you spread the damage across a large number of ships compared to the numbers of Hoshis present, a TEC fleet can tank a lot of damage.

Advent has more problems than just LRFs dominating the game once again;

-Advent has the least and most expensive economy upgrades.

-Advent's civilian 'advantage', early culture and more culture upgrades, is garbage as culture has little impact on the game.

-Advent has the worst superweapon.

-Advent's envoy abilities suck, and have pacts that only really benefit themselves (beam, culture).

The root of the problem is that Advent has been OP for so long that their weaknesses always got overlooked.  Now that Illums are no longer the scourge of the game, suddenly their weaknesses shift into focus.

It was beatable, though a bit on the strong side.  The bigger problem was that it naturally lead right into illuminators, which proceeded to kick the living snot out of you.  Skilled TEC players could handle it by leaning heavily on the Sova, and Vasari players... well, I repeat my 1.181 axiom for the Vasari vs Advent matchup: build a starbase on someone's homeworld asap.

I personally think this would have been fine if they'd just reduced the Seekers shield and armor values so it wasn't such a tank.

Not saying it was easy or balanced, just that Vasari could pull it off.

In 1v1... would depend heavily on the map, but I wouldn't say it was unbeatable.  Most 1v1 maps are sufficiently spacious to give Vasari breathing room before the Advent hits.  Trick as Vasari was to get out those phase missile upgrades and get a sufficient bulk of sentinels and assailants.  Once you had a sufficiently solid mass, Advent had to upgrade to their more powerful units because the low-tech stuff wouldn't handle it anymore.

Yeah, I must have been noobing it those several times I couldn't figure out how to deal with the mass of 80 seekers 50 disciples and other stuff.  Like I said, build a starbase, get boxed in, don't build a starbase, there were always enough seekers around to make you never build assailants.  No Assailants means Disciples are dangerous to your carriers and flak.  Equal skill then = Vasari lose, either fast or slow.  Team games were different, someone could be a buffer and Vasari would augment with Starbases.

AGAIN, I AGREE ADVENT IS A BIT UNDERPOWERED RIGHT NOW SPECIFICALLY VS VASARI.

I played a fair amount of 1v1.  Vasari was a lame duck a couple patches ago, all theorycraft aside.  Not only could I not beat people, but I couldn't see HOW to beat people in a 1v1, unless of course I seriously outskilled them.  The equivalent Advent & TEC fleets using scouts as support ate the Vasari fleet alive.  Why do you think everyone did it?  Only the Vasari starbases could hold out.  Why is this so hard to believe?

Re-read what I said; I said the bigger issue was that the scout/disciple rush naturally lead to illuminators.  On its own, scout/disciple was perfectly beatable, the natural transition to illuminators is what made the kill every time.

Near the end of 1.18, I stopped using illuminators entirely (outside of the mirror match where it was required).  While I'll definitely agree the scout/disciple rush was on the strong side, it wasn't unbeatable and a skilled player could match it within 10 minutes if they were quick.  The real issue was the transition to the bugged illuminators; take that away and this is just an overpowered opener, not an end-all by any means.

Well I would suggest that Darvin and Cykur are fairly well-matched as players, though perhaps Darvin has a regrettable tendency to insist that he gains no advantage from fighting on maps he has designed himself.  It would be good to have a downloadable series between them.  The players have badly let the developers down in terms of series replays to allow the proper discussion of Sins balance- with one or two very laudable exceptions there have been far too many opinions offered and far too few replays.  Starcraft got where it has because of the continual stream of high-level 1v1 play offered up for analysis and comment.

My impression is that there are really two different types of balance in Sins, 1v1 on a 1v1 random or custom map and one player against another as part of 4s or 5s.  At close range, with few planets to contest, Vasari had the option to starbase gravwells which would make them more or less immune to scout/disciple tactics- and feed was also available to make starbases easy to construct.  Vasari turrets can also be quite nasty.  Of course, the bugged illuminators could always crash through starbases anyway.  Illuminator tactics were like sentinel tactics in the current version- they were effective against ships that they had no business being effective against.  TEC is a gamble in the 4s/5s, they can defend effectively but the real advantage is if a teams TEC is in an 'eco slot,' which doesn't translate to the 1v1 game proper.

Proper 1v1 is like a different game.  It's also the only type of game you can use for balance purposes, as all random team 4s or 5s are skewed by game situation, its just silly to use them for balance.  Vasari used to have problems in random 1v1 because there often weren't enough neutrals to compensate for their economic disadvantages.  As random 1v1s favour multiple capships more, Vasari have an even greater advantage with their Skirantras on 1v1 maps, though somewhat offset by the need for more starbases- though Sins random 1v1s are very often extremely chokeable.  Advent are far less vulnerable to early attack and with time to tech up are stronger in proper 1v1.  TEC seem to suffer on 1v1 random maps, perhaps because Advent are peculiarly vulnerable to Vasari and not to TEC. 

I often wonder why the developers imagined that the game was ever capable of balance, with one of its factions made so generally vulnerable to another?  It would be good to have replays of two of the top players in a series where they took each faction in turn, perhaps six games in all, or nine with mirrors.  Then it might become clearer how the theoretical advantages worked out in practice.

I really dont believe the game is supposed to be balanced race to race.Advent are geared to counter tec,vasari to advent and tec to vas.The problem with balance now is that some of the advatages over the others are rediculous.Like way out there.For instance we all know the skirantra is totally out of line.3 caps fielding 50 bomber squads mid game come on.Phase missiles are there too.Not to bad for tec because of hoshis early on.I think advent vs vas would be much more balanced if subjugators worked for a heal ship.If they worked more like hoshis.As they are the cap ship is dead before the sub turns to the cap.Subverters+mines, kosturas and so on.Also TONS of tecs are worthless in this game for some reason and were never  fixed.I do think that this sort of race to race imbalance makes the game interesting especially in big team games.

Race imbalance is a lot more acceptable with more than three races.  For just three races, everyone has to have viable options.  TEC vs Advent & TEC vs Vasari are ok matches, but Advent vs Vasari, Advent is pretty hosed.

Actually yes, I was going to voice the exact same point Cykur.

In the Diplomacy section, Des and I just recently spoke on Age of Empires 2. In that game there WAS civilizations that seemed geared to tackling another civilizations (e.g. a heavy cavalry civ was always going to find it easier chasing down the lightly armored archers of Britain than facing the camels of Persia) but the reason why it worked (beautifully) was because there was sooo many civilisations (around 14-15 I think in the expansion).

I can see that in Sins the developers wanted the tricky, mobile Vasari have an advantage against the simple straightforward brute force of the Advent but their mobility and powerful phase missiles were not so effective against the high producing heavy armoured TEC. And that TEC's numbers would not be as useful against powerful mass effect abilities that the Advent are known for as well as their 'victory by attrition' style being handicapped against high dps advent ships.

It really seems lots of the game's mechanics were at slightly geared like this. Whether it brings balance in 1v1... idk.       

I ran with Assailant/Sentinel/Skirantra in the 1.18 Vasari vs Advent matchup.  Sentinels and fighters (from Skirantra) to kill scouts, Assailants to kill Disciples.  Early on, an Advent will just rush your assailants and knock them out, so it wouldn't work in small initial skirmishes, but if you build it up, your area of effect damage takes over and the Advent scouts will be on the losing side of this trade.

Anyways, as I've already said, we're beating a dead horse.

I don't recall phrasing it that way.  I think I may have said that about Fallen Paradise, which is a map so simple there's no conceivable advantage to be had (we never played that one).

While I'll agree there are far more variables in a large team game, I wouldn't say they're irrelevant from a balance perspective.

Strongly disagree; TEC can get a pretty wicked economy rolling on a typical random 1v1, and this usually leads into a brutal LRM push which is nearly unsurvivable as Advent (unless you managed to field fast Destras) and easily puts Vasari on the defense.  However, it's all downhill for TEC after that, so they better make that initial push count.  The other factions will royally kick your ass if they repel this push or recover from it.

Unfortunately I've cleaned out my replays not long ago when I reinstalled, so I don't have any where I can show you me rolling with TEC against skilled players in a 1v1.  To be honest, when I post replays, almost no one downloads or watches them.  In the old days, 20-30 people might check out one of my replays, but the last one I posted I think 2-3 people downloaded it.