I'm sorry, is repairing any critical in 10 seconds not fast enough for you? Nobody else can do that. The closest you have to that is Elite Armour's Critical Repair, but is more expensive, takes much longer, and triggers an abandon critical if the vehicle takes damage.
I suppose "different armies have different advantages and disadvantages" will fall on deaf ear with you?
And in regards to your next post, I don't see ost having LMG and shreck upgrades being disabled when you pick CAS or other muni convertion doctrine, or OKW having vet 5 disabled after picking specific doctrine.
Why do you believe picking doctrine should disable stock core mechanic of a faction?