Don't let your cap ships get near battles with too many lrms, bombers, or heavies on the opposing side.  Keep them in the grav well near a phase lane and far from the action if you really want the exp from the battle.

Don't start with civ labs if you're close to an enemy in a team game.  Some exceptions apply, but you'll have to just play more games to get a feel of when and when not to do it, depending on your race, your opponent's race, and the distance between you.

Don't not research phase missile upgrades. (double negative intended)

Don't let your cat jump up on the keyboard and shut down the computer, don't ask me how I know  .

Don't ignore your economy.  SINS is like any strategy game.  Economy is the key.  A strong economy allows a strong fleet and research base.

Don't forget to upgrade Civilian Infrastructure under the Planetary Development menu when you acquire a new colony.  As the Vasari especially, don't let your expensive ships get destroyed.  Also, don't build a bunch of Skirmishers.  They're inefficient for the cost, and easily destroyed by the enemy.  Don't neglect the low level phase missile upgrade either.  Not only does half of your fleet use them, but their upgrades provide more bang-for-the-buck than any other weapon upgrade in the game.  And don't forget to build more Navigators in maps of appreciable size.  The Vasari will want to quickly capture neutral extractors using their scouts and hold onto them as long as possible. 

Don't just spam LRF.  I took out an Illum spammer today, 40+ at once at one point, using fighters and 12-15 illums backed by a Mothership and Halcyon and some Drone hosts. I kept waiting for him to build Defense vessels and he never did.

Don't just FF (focus fire) on his capital ship(s) unless your are sure to get the kill. I had two capital ships a Mothership and Halcyon and rotated them back to my nearby world to swing by some repair bay(s) and back into the action while my fleet and fighters picked off his illums.

Don't let a capital ship with low health simply jump away. If you see him going to jump, jump some of your own fleet with him to intercept and keep some back to keep hitting until he jumps and follow to get the kill. Alas he lost his mothership to this.

Don't undervalue PJI (Phase Jump Inhibitor). Adding 700% jump time can be great if they fail to notice or are put on the run. I took out a running low hull level 8 Akkan (did he neglect armistice?, maybe) when he tried to escape by jumping through one of my roids with a PJI while I was following.

Don't get caught in a PJI. (see above).

All of its abilities require antimatter, and many of these are far less effective than abilities on other cap ships. Gauss rail gun in particular is considered a terrible abilitiy because its damage is effected by shield mitigation. Flak burst is the only thing that is occasionally worth while, but there are easier ways to handle strikecraft swarms, included the far more versatile Sova Carrier.

Other than tanking damage, and providing a bit of anti-strikecraft duty, the Kol's regular weapons are weak and dispersed in all directions.  Its Gauss Rail Gun is total weaksauce compared to the Marza Dreadnought's Radiation Bomb as well.  A level 3 Radiation Bomb deals less initial damage to a target, but then deals 210 damage over 10 seconds to all targets in the area.  If you're facing 30 ships, that is 6,300 damage applied to a bunch of targets.  Those same targets are also susceptible to Missile Barrage once the ship hits level 6.  Meanwhile the Kol's Rail Gun zaps its entire antimatter reserves in 15 seconds, dealing a third of the listed damage since shield mitigation deflects the rest.  While the Marza scales to meet the enemy threat, the Kol does not.  If it were up to me, I'd triple the damage output of its forward beam weapons(maybe even quadruple it).  That would put it more in line with the Marza's regular missile volleys, and make the Beam upgrade worth more for the TEC, especially considering it is tier 3 and 4.  It would also make the Kol a mirror opposite of the Marza, having it specialize in anti-capital warfare. 

All that said, there are ways to maximize on the Kol in the mid- to late-game.  The Dunov's Flux Field comes to mind.  60 seconds with -75% antimatter cost means the Kol can fire 12 shots of its Gauss Rail Gun in rapid succession, as well as 6 blasts of Flak Burst, along with its shielding.  The TEC antimatter regen buff within their own culture helps a good deal too.  For that matter, a starbase with Docking Booms provides similar support.  Finally, Finest Hour gives its weapons 60 splash damage to nearby enemies.  That helps it propagate damage in combat. 

It is just that, as a starting capital ship, the Kol is rather wanting.  In terms of raw combat prowess in the early game, a Sova Carrier goes much farther.

I use the Kol as a tank while leaving carriers and lrf's behind it and keep only flak burst active to hit the fighter/bombers that are trying to get by to the ships behind it..  Use other cap ship abilities to enhance it from behind as well.

In actuallity the lamest cap ship has to be the anturak marauder.  It even has an ability that hurts your own fleet!!(the make invulnerable one)  It makes your fleet effectively smaller helping the enemy(as long as they notice which ships are affected) Suprised this hasnt been complained about before or changed to only affect enemy ships.

It does work somewhat against easy AI but any human opponent will quickly concentrate fire on the units not effected and then mop up your other units once the ability wears off. 

Oh no, this is the best a battleship in the game! Its one of the best capitalship killers avaliable and is even harder then the Kol to destroy. I usually have one of these as my third capitalship as Vasari.

The antorak is a great ship.  The problem is, you want it to be some massive dps fleet killer - of course it isn't that.  And the reason the MP folks hate it is, it is never going to have any use on crowded rush maps.

If I were playing a large, noncrowded, non-rush map, it would be one of the first ships I would buy.

Phase Out Hull is also handy to semi-permanently remove an enemy capital ship from the fight.  In doing so, you also drain its entire shield supply.  You also get to use it to prevent or delay focus firing on your own capital ships, or to bypass strikecraft bomber runs when they get into weapons range.  Lastly, you can use it to effect rapid repairs on your own ships after a scuffle. Okay, you can also glitch out pirates with it as they try to phase jump away. 

As stated, it loses efficacy in MP because it lacks any serious combat impact.  It is meant as a sort of rapid fleet transport.  Phase Out Hull also helps against sustained abilities from enemy capital ships, e.g. Missile Barrage, Drain Planet, Cleansing Brilliance, Disintigration, Finest Hour, etc.  It can be helpful as a third capital ship in a larger game though, when cap ships gain experience fast enough to fly through levels in a short time frame.  It is somewhat context specific though.  Skirantras, Devastators, and Evacuators are still the prime choices for capital ships.  The recent ability buffs keep it from being totally worthless IMO, i.e. the 200 shields thing, and the increased turning speed afforded by Distort Gravity(it decreases phase jump departure range too).  Subversion still sucks though, since it only affects build rates.  I'd make it cut tax income in half as well.