You got a lot of different questions/variables...let me try to answer as best I can...
1) You list of parts sounds good...It'll definitely give you an added boost without getting real crazy.
2) If you really want to take advantage of bean's injectors you will NEED a chip from Tony...He'll custom program that thing to your truck with the mods you have. The edge will not utilize your trucks mods like a chip from Tony will.
3) Unless you are already in possession of a GTS kit from Geoff you may have a hard time getting your hands on one. For one, his website is now gone, and he has not had a real strong presence on the boards in the last year or two. You may want to look into fabbing your own kit...or getting one from Banks or Hypermax...~$500 as I recall
4) Your HPOP may keep up, really depends on the condition its in. Some guys run Stage 1's pretty well with the stocker. However, when I chipped my truck (~125k miles or so) (stock sticks) the extreme setting would throw a CEL for low HPO...I upgraded to a 17* Pump and no more light. So like I said, it'll depend on your pump and the condition its in.
5) As far as mileage is concerned, it going to depend mostly on your right foot. Chances are with these upgrades, if you drive the same way you do now your mileage will IMPROVE with the new parts.
Hope that helps some!