I know simulating collision damage was tried and failed, but with our current unrealistic boarding capabilities or sometimes lack of (determined defender), perhaps it’s time to relook at some options.
First, I don’t know if it is always possible for the game to determine who rammed who. I also don’t if the game can determine the speed of the collision. But...
Here are some options:
Damage and leaks to both parties, the lighter ship sustains worse damage. Possible immediate rigging shock as well.
But even more important and perhaps easier to implement. A use for the BRACE COMMAND. If there is a strong enough collision and your crew is not braced you receive significant crew damage and go in to crew shock.