So I just played the 0.1 version of the game and thought that it had much more realistic crash physics and thought "oh! these physics would be sick in the current version of the game!" Now I don't know how hard this would be to implement but It'd be sick to see this in the current version of the game.
I... um... what aspect of the "physics" exactly did you want? The physics are... well... they are just that. They are physics equations from real life. The tire model has gone through quite a few changes over the years which did change the feel massively, but the actual physics of the rest of the simulation have stayed pretty much the same (other then added simulation aspects like engine physics, drivetrain physics, electrics, and other fun stuff like that). Now that being said, the spring and damping settings have changed over the years. The nodes, node positions, node weights, the contactors, the aerodynamic drag, all the aspects of a JBeam of a vehicle (never mind new JBeam features) have changed which massively change how the vehicles behave massively. This was done as the Beam Team improved their understanding of vehicle construction, material properties improved, testing results, collaborations... basically just tons and tons of data gathering throughout the decade. Now the actual way that the calculations have been done over the years have changed massively. New ways to do the math, Reductions in calculation steps, Simplifying equations (numbers that cancel out in equations by the end), better ways of doing the math (matrix algebra and all that fun stuff) which reduces the calculation steps that the processor must take to get the job done, but other then running faster the actual answers are the same.