You may find it not related to thread but Arnoldio was working on a vehicle physics mod that could actually do the thing and find a right compromise. I've wrote post about it, but lost it by closing a tab, hope I will cover again what I had to say in short, maybe elaborate later.
Personally I've found vehicles having too much mobility (not just heavy assets) - top speed, acceleration, climbing, etc. when compared to INF.
The thing is that terrain should affect any vehicle waaay more than it affects infantry in a matter of mobility, eg. mean speed through rough terrain is proportionally much affected in case of a vehicle.
BF2 engine cannot simulate detailed aspects of a terrain - and it is doing so now like all the terrain was made nothing but concrete with a nice grip. Not realistic, huh? Much older game - ofp:cwc was able doing that by implementing some kind of velocity maps to the terrain (and pseudo bumps offroad), wasn't a perfect solution but simple and it was working - eg. you can move faster on roads, don't know if it's possible in BF2 - it doesn't matter now, it's possible to make some workaround to achieve kinda same goal - like Arnoldio was/is trying to.
As I remember he was trying to reduce overall acceleration, make vehicles more prone to terrain shape, maybe also reducing/modifying top-speed.
On the other hand - reducing acceleration, soften suspension would make drivers feel that they're operating something that is actually heavy and valuable, would be a nicer feeling though, not just toy-like.
Like it was with inf damage model, we cannot put raw, theoretical values into game and voila. It wont be realistic and moreover, wont be fun because since game cannot simulate every co-related aspect we have to simplify/randomize things in a some kind of statistical way. Mobility is one of the aspect that seems to be overlooked, not just in PR. We just used to it. Even in a combat situation you would be likely not doing pedal to the metal things often, risking your vehicle and crew (except here would be a garry truck).
How above is related to the thread for me?
With this 'reduced' mobility of vehicles, infantry could eg.:
- predict vehicles movement better
- with a more precise prediction can make more effective ambush (HAT/mine)
- have more time to prepare defensive tactic, eg. take cover

- make more use of a terrain
- make vehicles more vulnerable to unguided HATs/slow-moving projectiles making those kits more 'noticeable' @Rabbit
and other things that You can think of
On flat maps like Kashan there would be not much difference, on the other hand on bumpy-forest ones difference should be noticeable - that solves some of Your concerns mentioned earlier.
It would be also kinda more realistic to spot vehicles where they are suppose to be. The idea of convoy could gain some importance.
As an inf player I have to say that playing vs. heavy assets is fun, but yes - I think they're kinda OP most of the time. Removing them drastically is not a solution, because we could loose a lovely property of PR.
Can't say much what I can expect from a crewman point of view, but don't think those changes would make PR less fun for them - heavy assets would be still playing a crucial role on a battlefield, maybe would be harder for them - but isn't game about being somewhat hard-rewarding?
A lot of words, but I'm not telling You about big changes, just slight optimizations leading towards reality/fun/whatever.
Keep in mind that changes proposed by Arnoldio were not this plain as I've described here, I've also extrapolated it cause I've found it useful in this thread. Here's original thread:
https://www.realitymod.com/forum/f388-p ... ments.html