It is indeed a big danger to make this OP, but the alpha testing could not bring any light to if its actually true or not, so i hope there will be more testing in the beta to show if it is, or not.
This is not a change that will go 100% into the game, its there to be tested.
However you need to think about that the difference is not that big - you can already rush a tml and assist two missiles before the enemy is t2, it only takes a few seconds, so the actual change is that cybran has this few seconds (depending on the amount of assist on the tml) less than other factions to get a TMD up.
Its not a difference between making cybran HQs able to kill easily and others not, its a difference in time they have they can afford to be later on t2 than the other factions.
I understand the "healing between missiles" problem, but can't you give it 6100 hp? Two missiles will kill it, 100% of the time. It won't die to one missile 100% of the time.
The whole idea behind the change is to do exactly that though - to make faction HP matter more and be different, and as part of that, make cybran buildings vulnuable to TML as faction weakness. Two missiles already kill an HQ right now, so there would be no significant added weakness.
The healing between missiles is more for the higher tech HQs.
I kinda like the faction direction for cybran: best TML, but very vulnerable against TML hits themselves: Both T3 mex and T3 pgen die to 1 TML aswell.
Thats the idea. Maybe some of the cybran TML nerfs could be reverted to even out the new disadvantage, or other ways to finetune it. The goal is to bring more faction diversity and make hp differences a strategically important part of the game. Maybe this particular case is too extreme, maybe we can make it work. The test looks bigger than it is as mentioned above, the 6000 hp for t3 mex and t3 pg are maybe bigger, and even more so together with everything else its maybe too much at once.