I'd find it useful to have a command to copy the running arpeggio into a sequence slot.
This would be nice when you have a arp going you like and have it also "programed"
in a sequence (which also could be edited afterwards in seq. mode or via MMC, handy).
For example hold shift and the record button (when in arp mode) to copy it into
the sequence slot corresponding to the arp mode currently selected