Yamaha DTXpress/DTXplorer/DTXtreme

TP100 is a nice upgrade I think.  I use one on a snare stand.  Make sure you get a snare stand that will go small enough if you go that route.  I don't know what the TP10 is (a triping mistake?).

All inputs on the DTxpress III are dual zone except for 2, 6 and 7 which are 3 zone.  So, yes, you can have two 3 zone cymbals.  

I never liked the TP65 as a hihat.  I swapped to a PCY65s almost straight away (dual zone).  

If you do upgrade you can use the old pads as an extra tom, another ride or china etc.

Keith.