Asking other owners for their comments and pictures is probably your best starting point.

I agree with Chris on this. I have lazy jacks on my boat. They work well, are cheap and easy to set up without modifying the sail. In your case you are probably looking at a new main anyway since modifying the old one would be money better spent towards new.

If you go to mid boom sheeting it is best to spread the load over some distance by using two or three blocks at least a foot apart. That's what my boat has. I have read that mid boom sheeting has more failures than end boom.