So a sequence wouldn’t be able to bring in new tracks/instruments to or remove them from a composition? It would only be able to change the notes an instrument was playing, so long as it was already playing something?
Personally I try to avoid using patterns if at all possible, as we can’t label the patterns individually and they take extra work to access compared to tracks. I also have in the past had problems with pattern switches not respecting my settings and always being immediate instead of delayed to the next bar. They may have fixed that bug by now though.
If the problem is that you don’t want sequence changes to screw with the playback of a pattern/track that’s already in the middle of its loop, that is possible by choosing an appropriate Track Run Mode for your use case. It sounds like FREE run mode is what you want though, and that’s the default mode so I’m guessing this is not sufficient for your needs.
EDIT - Oh i see what you mean. Like if you’re live manipulating a previously-saved sequence, you don’t want every automatic sequence change to suddenly discard your active track choices and force you back to the saved state. Yes, that is actually super annoying and can totally wreck a live performance. Basically, if you use SEQ PLAY mode, do not try to make those sort of changes while the sequences play through because it will end badly.