The biggest difference between the way fire was before and the way it is now is that the fire pools can potentially inflict a lot of friendly fire kills. Using any form of flame vehicle means your own infantry could be in a lot of danger if they're anywhere near it.
It also means flame vehicles are much better vs team weapons than infantry, which can be problematic because it leads to vehicles countering their counters: AT guns. The crocodile is obviously the biggest offender.
I think the damage over time design can create interesting gameplay, but right now almost every flame vehicle feels very strong, and if the KV-8 is borderline OP, the crocodile must be completely over the top.
The wasp though
