Heh, I like the damage from ramming idea, the NPC fighters that continually hit my Cruiser during missions are sure in for a shock!
Also the mining thing.... good idea.
People will still be able to mine, but they are going to want to have a Trader as well, for when there are too many people mining in "their" field or perhaps people will start setting up a Traders with a mining turret.
Interesting thought.
Edit: on another note.... bugger. No more mining helium in my GB's while I'm putting in 'flight time' to keep them current. Can't afford to put a mining turret on either them, the reduction in firepower is just not worth the ability to pick up free stuff by mining.