Hello!

I have noticed that vehicles can move forward even on neutral which shouldn't allow me to: Car moving in neutral

Cars seem to be "floating" above the ground and not actually keeping contact with the ground, this could be a reason why the cars tend to spin at high speeds and the RPMs keep jumping when driving.
Car at high speed

There's also times where they feel like they're on ice after just tapping the handbreak or making a tighter corner, I do like the feel of losing traction, but at the moment it feels like you have to almost stop in order to turn. I believe making the cars stick a little more to the floor will let them be more "playful" where you can abuse the corners, have more stability overall and make driving more fun in general.
Cars sliding

Thanks,
NAyRAM