About Kpen's proposal I think it would be the best if it had a normal Tiger call-in that gets buffed for Ostheer as well.
No more command tank cheese pls
Especially that OKW already has Command Panther, there is no need for another aura call-in unit. Although on the other hand it would be good that OKW Tiger would be diffrent that ostheer version. It doesn't have to be better or worse - just diffrent role on the field. For example OKW version should be more tanky, focused in breaking enemy defensive lines where command Tiger should be more supportive, focused on mainly long range fights.
Another fact is that I assume that TigerAce gonna be revamped into the Command Tiger tank (another overlap with ostheer faction). Of course unless it will be replaced by King Tiger.
It's a hard job for balanceteam - to make 2 diffrent Tigers I from currently existing.
I would suggest a list of abilities for new Tigers that could be used(seperate for each):
1. camouflage - tank is invisible while is stationary. First shot gives extra penetration, accuracy maybe damage.
2. critical repair - same as in EliteArmor
3. MG42 or TankCommander upgrade - again, same as in Elite Armor doctrine,
4. Smoke shells - can drop smoke shell like sherman tank or fire smoke round as UKF can,
5. AI round - can fire AntyInfantry shells in period of time (or single shell). Larger AoE and it can suppress surrounding infantry (but make less damage),
6. KingTiger vet3 ability (sorry but forgot the name) - extra reload but cannot rotate the turret more than 90 degree,
7. Target Weakpoint - disable the turret of enemy vehicule,
8. Inspiration - temporary increase the stats of surrounding units - for example reload and speed or maybe reduces reciving accuracy. Aura of command tank becomes a free BUT time ability - sort of like commisar has it now,