Honestly I would probably just remove the Battlephase 2 requirement and let Ostheer have a Puma within Tier 2, maybe increase it's cost a bit to compensate I feel like 80 would be fine. I think the old call-in Ostheer Puma was that cost. Right now it takes OKW about 130 fuel to obtain a Puma, with these changes the Ostheer Puma would require about 140-150 fuel which I think would be reasonable. If the doctrine becomes too powerful finally tying the Command Tank call-in to Tier 3 I think would be a good nerf just to prevent people from Puma spamming into Command Tank call-in. I feel Ostheer is the faction that could really use the Puma as I feel they struggle harder against light vehicles than OKW does. Usually OKW can at least get a Panzer II to tank damage for the Rak's whereas the Ostheer light vehicles aren't able to efficiently defend the Pak unless you build multiple of them which delays Tier 3.
Well said, combining a techless AI and AT vehicle was what made old Mobile Defense broken. IMO:
- Make Puma buildable from T2 at 5 CP. Possible limit of 1 on the battlefield.
- Allow the CP4 to be called in after constructing either T3 or T4. Slight cost adjustment.
- Optional: Turn Reserve Osttruppen into AT-rifle Osttruppen squad at 2 CP for 300 MP.
Puma would have to be build like now, so it doesn't arrive instantly which was a problem with old Mobile Defense. It's behind T2, to not make T2 skip strats too viable.