How about a Rammer weapon that also poses as extra armor

This would of course be the weapon so perhaps it would take up any 2 ports such as 2 small or large ports and increase armor buy a moderate to really good amounts. Ramming would cause damages to the opponent but not to your own ship.

I have no idea about the logistics of how much damage a RAM hit should be

Eat your heart out Mad Max!

We actually did have that in the early VO.
It was called flare ramming. Back then there was no rocket backsplash that could cause damage to your ship so we run triflare valks and rammed serco SCPs to death in Deneb.

The silliest trick was a warp-flare ram - charge at the prom, fire flares at 10 m and initiate warp jump at the same time.
Fun times.