RE: size of esc, bigger is better?
The fw190 gws will be a rock allright,,weightwise that is..a 2100 with a 36 ESC is not an ideal set up for it,that stuff will run an Eflite 480 easily.
If you want that thing to rip then keep it light,get the right motor with appropiate KV rating and prop it accordingly,small diameter high pitch, battery should probably be a 17-1800.Not trying to tell you how to build,just thought you may want to rethink it,or use the batteries and esc in a different airframe.