For next version, please make it modder-definable how much damage things like impact damage do, based on a multiplier. The file would also allow for global overriding of settings like impulsefactor, etc, and any other physics-related stuff you can think of that can be done without too much work.
See here to understand why:
http://taspring.clan-sy.com/phpbb/viewtopic.php?t=6943
It could be defined per-unit too, but I know how certain people feel about more FBI tags...
