whoops, better reply to the topic question.
You want cheap and u want variety with x0x programming on the fly?

Go a Korg ES-1 (or preferably new version but that aint cheap)

Es-1 is dirt cheap, quick and fun to jam and unlimited sound ptoential cus it uses samples which you can ofcourse change

It'll go well with the analogness of the xbase AND it sounds crunchy cus its only 32khz.