But if you are not making such a build , it's a net gain while the mecha lasts, in particular when you take in account the mecha auto-ejects the pilot when it reaches 0 HP.
That wouldn't work well. The android would normally die before the mecha breaks or at the same time, at best. It won't get to use the auto-eject.
Not using OwtM gives your own HP + the HP of the mecha before you die, since when the mecha is down you're ejected. An android with OwtM has only his own HP and doesn't get a free escape with the auto-eject if there's an attack that would kill it.
You get a mecha that has a more HP than the norm (if the android invests big in his own HP score, which he has no choice to do if he doesn't want to have one less ability) but you die faster in it.
Even without heals a critical hit on a mecha inflicts more damage to the android than it would normally receive.
If somehow the mecha is destroyed and the android inside is still alive, it would be in a much worse shape than another pilot.
Promoting a mecha build that doesn't rely on self-healing? Crazy, I know. Whoever heard of mechas that can't reconstruct themselves on the fly? It's almost as several of them are supposed to be inorganic machines.
Your reasoning was that you didn't want to encourage mooks healing the android to save the mecha. You just have to prevent heals on the android from affecting the mecha. Now you're still encouraging mooks to heal the android within so that it can keep up with the mecha's heals.
A PC that doesn't have any way to heal his mecha, himself or by an ally, is highly unlikely (they'll likely get at least 1 spirit to heal). Mostly considering that without healing a mecha will have a hard time being used through multiple encounters until it gets back home for long repairs.
In-combat healing is also rather common in DnD all around, if only from a dedicated healer. With this campaign setting giving tons of means to dish out big numbers for damage, this is no less the case. Sure, an android could use Guts while not in OwtM, but then if it has Guts why even bother with OwtM.
Otherwise, it could also return to the mecha using the android's HP like it did before and the mecha being destroyed if the android dies, then add the effect that the android piloting the mecha is targeted as if it was the mecha itself and so can no longer be affected by effects that wouldn't affect the mecha, which would prevent any extra method of healing and buffs from within the cockpit that isn't available to any other mecha (and prevent most buffers in the cockpit from affecting the pilot to buff the mecha). It also wouldn't benefit from regeneration twice off Machinery Warrior since multiple regeneration effects already do not stack and wouldn't be applied to two different targets to combine the effect.
And if you want a self-healing android build that badly, that's what Machinery Warrior is there for.
For now I'm interested in the android becoming one with the machine properly. I could have made a stronger build without the android race to start with but I liked the idea of One with the Machine for my concept and I have so much more stuff to work with now.
Machinery Warrior starts at level 11. Bit late for the android to start trying to keep up with an healed mecha so that's out of the question in campaigns in the lower levels. I'll probably level dip in it all the same, but not for the regeneration, which'll be redundant in my build anyway.
Born to Fight featThe arsenal surge for Mega Booster and TROMBE! do not have a duration.
Innovade featIs there supposed to be a limit to how many mechas can be piloted by this? You can fit quite a few in 20 feet plus 5 feet per Pilot level and even more if you use the Einst Queen Infiltrator trick to turn that range to mecha scale.
Also, if a mecha/machine becomes unattended within range of two Innovades, which one controls it? An opposed charisma check, perhaps?
Oddly, the benefit feels like something machines should be good at too, despite it being normally a 'human' thing. Androids are bad at it though since they can't use charisma well.
Showtime StarPretty cool. One More Time only covers the cost of the weapon, right? Not the maneuver that triggers it. At least that's what seems to be intended the way it is presented. Very powerful and maybe not too much so as long as it happens to only one attack and not all of them, if a maneuver offers a bunch of shots.