Analogue-sequencer

just a request/suggestion from a current non user to not skim on the
user interface side of things. Judging by the prices used P3s are
going for you can easily target this to the 1500$-2000$ price bracket,
which should provide enough margin for a non-compromise UI design. 

I keep dreaming of a P3 with a graphical read out of the current
selected lines. Either using values on LCDs or having those endless
knobs with LEDs around them...

and also lots of dedicated buttons for specific functions, like < >
buttons to scroll x0x pages, dedicated buttons for part selection, etc...