You are thinking in the right direction, but need a little redirection.
Delta does a regrind for your cams. They run $165 plus freight. It gives you about 15 hp and it mostly a midrange torque grind. You won't lose your bottom end.
Unless you are doing the port work yourself, don't waste your money. There are minimal gains to be had there.
No point in stroking your block to 2.5l. What you want to do is find an EJ25 shortblock and just swap your heads and everything else over to it. This would put you in the 11.2:1 CR range or so. Along with those cams, you will break 200hp at the crank. We are currently building one of these in my garage. The engine is complete except we are waiting for the cams to be delivered. If they come today or tommorow it will be in the car and running by the end of the weekend.
For more, do a search in this forum for a thread about a high compression frankenstein build. Frankensubbies rule!