Personally I find the pattern mode really useful, especially when coupled with "save and take over patterns". If you haven't tried it, it enables you to assign changes in your song to the 16 GP buttons. For each of the 16 slots, MBSeq stores mutes, can send program changes and mixer maps and then trigger 4 pattern groups (i.e. choose 16 tracks). You have 16 slots like that (i.e. 16 changes) per song. I used it for a live set earlier this year and it was great, sending program changes to all of the midi kit we controlled was pretty much instantaneous and with 3 MBSeq songs set up like this we jammed for an hour.
I'm not sure if that would match your snapshot concept, but I'd give it a try. It enables you to decide the structure of the song pretty live IMO :)