Innate regen is in itself okay, but the DC hasn't been an interesting chamber since god knows when anyway. I'd prefer an extra percent or so on Gorge heal together with the infamous "focus healspray" - that way we would skirt boosting the most powerful chamber, the MC.
And why in the world the 30% visibility thing would be necessary I don't know - cloaking is already a mighty nasty upgrade. It might even work okay earlygame, but in a midgame scenario with MC/SC its just another in a long, long string of 2 Hive advantages, along with double the spawn, teleportation, leap, bilebomb, umbra, metabolise, stomp and the armor bonus.
The only really dramatic imbalance is midgame marine balance - they're fairly pathetic, and there is about one strategy with a high rate of success, thats prototeching it up. They're already spending big to do that, together with fielding HMGs and welders, a phasegate, siege equipment and medpacks (until the appropriate prototech is available, meds cost quite a tad). Now lets have sieges do no splashdamage, and make them instantly only half as effective - sounds like a winner to me.
@Ben:
Wait, the PTs played combat and thought the aliens needed boosting? Wowzers good sirs, thats just an impressive failure of reasoning.