1. the TFS stage 1 over a stock cam? Yes it will increase performance and I would recommend it. Just make sure you have enough clearance between your valves and pistons. It is a good cam.
2. I would not recommend milling heads for any performance reason at all. The value of your heads will drop considerably, you won't gain much performance, and you will probably have to buy new pushrods or you will have other problems. Milling should only be done to make the head surface straight IF it needs it, IMO.