If there's one thing that annoys me is the balance of the Heavy Cruiser. Ok, I understand that it's the most expensive cruiser in the game, so it better be damn good, but it has no effective counter.
Illum spam w/ shield/hull/damage upgrades and Deceptive Illusion + guardians (WITHOUT repulse) + mothership w/ Malice/Shield Regeneration is quite effective against HC

On the one hand you complain that HC have no viable counter, then you complain that the units which CAN counter HC are themselves too powerful. You can't have it both ways...
The problem right now is that carriers are too weak. They are expensive and not very effective. If they were fixed so that they were once more an effective long range frig counter (fighters), and more powerful vs HC (bombers), this would complete the balance imo and promote diverse fleet composition.
The balance would go something like this:
Long range frigs counter light frigs --> Carriers counter long range frigs --> flak counters carriers (vs strikecraft) --> Light frigs counter flak, carriers (vs the cruisers themselves), and support craft.
HC counters all frigs and cruisers except carriers (bombers)... and of course my wuvable super sexy and super upgraded illum/guardian/mothership fleet

Right now however, carriers are too weak and too expensive (as I said above) to be viable... and so you can see how the unit counter chain breaks down accordingly. Without carriers flak and light frigs really have no good purpose, and the result is you dont see them used online... except by noobs of course