If you are looking for a somewhat mild cam a 220/220 is generally a very acceptable cam. It will give you good power without being over the top. Your right on the money about the heads if you get them milled it will raise the compression and give you more power. You will need different length push rods with this change. Depending on how extreme you go might have to run high octane all the time but if you keep it to 11:1 or lower you should be fine to just run premium pump gas although E85 is a fun alternative. I would say you should get it tuned no matter what cam or head changes you make. It will net improved gains and actually make it safer to run. I would recommend some kind of upgrade to your transmission which I am sure is getting tired by now. A corvette servo is simple to install and will cost in the neighborhood of 30$. A good cam and tune package will make your truck a whole new animal for sure. If you stay somewhat small you won't need a stall, but for the great deal you can get from Circle D might as well save your pennies and toss one in there. A cam and stall will help you hang with most people you will find on the street and eat rice all day long. You can still tow and DD with the right setup. Don't cheap out or wimp out most of the time you will regret it.