I wonder, though, how a step-sequencer would work in a two-line display. That would be... err... a challenge. One thing you could do is implement it in the Editor-Librarian SW so you could update a sequence for each patch and then dump it. You could also implement an arpeggio editor. I bet you'd sell more E-L programs that way.
... And of course, you'd put me on the free beta list.

BTW, a Phatty with a built-in step sequencer would be a phenomenal board... even more than it is now. One of the only reasons that I've been humping my Fantom to gigs lately is for the sequenncer. If I could gig with just the Phatty, the Vox and a drum machine, I'd be thrilled.