Custom "physics" for simulating vehicles/tanks

Hi,
I’m making a game which has fair amount (as max of 100 - 150, average 25 - 50) of AFVs (tanks, …). For now tank handling is done. The movement and other stufff is done using unity physics (rigidbody, colliders, …), see Tank slipping on the slopes for more details. In the game, I’m simulating the world first and then replaying the simulation. During the test with 25 tanks the physics is taking on average 45-50% of the computation time (with 1 second of simulation producing the 3 seconds of “real” time, ratio 1:3). Which is quite a bit and the simulation is taking quite some time (and this is without any other stuff like AI, …). I’m aiming for the ratio 1:10 at least.

So my question is, if I would ditch the unity physics and simulate/fake the tank handling stuff (movement, suspensions, cannon blowback/recoil, …) by myself, would it be faster and worth it? Or it would have only marginal speedup? I don’t need realistic tank handling, it’s just needs to look somehow good.

Just in case, here is the profiler stats for physics:


Thank You