Z axis should be removed from the game (not scrolling into and out of planets, but controlling fleet to move in z axis should be removed).
Research labs could be play a more interesting role in the game than they currently do. If they get destroyed, then you should lose ALL research (including HP, etc) until it they are rebuilt again, not just a select few researched things like units or ability for cannons to fire etc. I mean, it doesn't make sense that, for example, units should still have higher than baseline HP or shields without a single research lab..Just my idea. I guess the exception could be ability to colonise volcs or ices.
Z-axis: Dont play with people who abuse it.
The Lab idea would negativly affect game balance.
Besides, it is even more illogical that ships would loose armor, just because the lab is not there anymore.
"Ohh, oh military lab just got destroyed.... lets remove our Repellon Premium Armor and lets replace it with the puny armor we used before."
Realistically you should be capable of building all ships after you researched them once, but here gama balancing (Kostura useful on multi star maps) cames above.
Besides, the lab balancing the way it is now is fine.