I think corvettes should be restricted so they cannot phase travel.  System defense ships--light and speedy at the expense of phase drives.  Helps cut the spam and abuse and puts them in a realistic niche.

That would be really bad for advent...they finally have a counter to enemy LRF spam...besides it's not like they are any more general-purpose then LRF.

 Corvettes really excel at fighting 3 enemies: LRF, light frigates, and capital ships, which particular emphasis on LRF(and to be a theat to a cap ship they need a large swarm of course).  They are countered by flak & AoE damage.  They also can have difficulty dealing with Carriers as their damage type is less efficient against heavy armor as compared to other frigates(also carriers have a bunch of health and can field 2 fighters, either of which is decent at fighting corvettes).

Also while corvettes deal decent % damage against pretty much everything 150%/125%/100%/100%/75% for light/med/heavy/very heavy/cap ship respectively their armor type take good damage from pretty much every damage type 133% from flak, 25% from bombers/cap ship & 100% from everything else.

Which basically means in terms of damage types corvettes are only actually at an advantage against capitalships, LRFs, bombers and light frigates.  Among these thy have a smaller advantage against light frigates.

Now there's definitely something to be said about their mobility, which is why I think fighters are also an underused counter against them(non-flak frigates often have trouble aiming at them).  Fighters & corvettes both do 100% damage to eachother, have comparable mobility, but the fighters are more expendable.

Also note some capital-ships actually aren't really countered by corvettes.  Any capital ship with AoE falls into this category, as no most carriers(as Is aid fighters fight on even grounds with Corvettes circumventing the capital ship 25% damage to corvettes).

I'm not saying the corvette balance is perfect, merely that there are counters so if we nerf them let's not make it anything too extreme(such as removing their phase engines).  One area I for one would like to see them brought down a notch is their damage to structures.  Reducing their efficiency against light frigates a bit would also be OK.

Giv ethe Advent an ability like the capture mines but make it capture corvettes.

Yeah, play with the armor bonuses... but leave them strong against the LRF spammers.

And a boost to flak would be most welcoming, they don't get any love anymore

I just did a quick test with TEC rebels and 21 corvettes took out 3 carriers (equal supply) with only a few losses, even pitching 25 corvettes against 4 carriers (50 v 56 supply) the carriers only won by one half health ship, so i dont think you can call carriers a counter to corvettes.

I'd agree that the best thing to do for corvettes would be give them their own weapon type and reduce it's effectiveness against heavy armour (which is heavies, carriers and flak (I think)).

With it's economy & strong early game units, the TEC never should have been given corvettes on par with the Advent regardless.  The Advent needed strong corvettesto essentially fix their early game issues(most notably lack of an effective counter against early LRF & lack of a counter to carrier rushes against other races with better economies).  In genera early game advent units have always been a bit better then the others per cost to compensate their poor economy(see their LF & scout for details).

That said, corvettes in general are too strong.  They real should have their own damage type- I'd think the same as know only drop their dmg against LF reduced to 110-115%(down from 125%) their damage against heavy armor to 50-65%(from 100%) & their damage against very heavy armor reduced to 75%(down from 100%) for starters.

  My point above is merely that the TEC corvettes also need sto lose some general efficiency(cost:hull ratio).  of course higher then it was pre-buff(they sucked before), but the current efficiency per cost is too much for an early game unit on a  race with the economy of the TEC. 

The biggest problem I see with disabling the phase drives of corvettes is they become a defense that can only be used on worlds that spend logistics on frigate factories(at the very least they would need to be producible at hanger bays IMO).

What about limiting them to traveling at most 1 jump away from a friendly controlled gravity well(that would cut down on their offensive uses but still allow them to travel around your territories)? 

My biggest concern is that corvettes fill an early game niche- which is precisely the stage in the game when players are most hesitant to invest much in the way of static defenses that only protect one well.  In particular corvettes were a godsend for the advent(more or less fixed their early game military issues), and the removal of the ability to use one force of corvettes to defend multiple wells we're left with a situation not much different then that before corvettes were added- all the opponent needs to do is attack a different gravity well(likely the next one over) as soon as the advent player invests the necessary resources to obtain enough corvettes to deal with the inevitable LRF spam or carrier Cap rush which the advent lacks another counter to.  The Advent doesn't have the early resources to fund a force of corvettes at multiple worlds to defend against a single attackign force.

Wouldn't that have a problem for the Varsri instead of the Advent? Since they are moving from planet to planet all the time, kind of a waste of resources, if they can't stay on planets and keep their ships there.