Steve, I use the economy morebeer 15 gallon kettle with a fixed face blichmann brewmometer, stainless ball valve, and I use a dome false bottom from morebeer. I mash with recirculation and a low flame to control the temp. Ive recently played with step mashing and it works but takes attention. A digital igniter would solve that.
So, get a 15 gallon blichmann boiler maker with flexible faced brewmometer and their false bottom, and a tower of power for temp control. Then when you up grade again call me, I'll take all of your hand me downs ;-)