How do I stop all playing patterns repeating (not abrupt)

[mvdirty]

If stopping the tracks one-by-one is not an option you could always create a row with empty pattern and SHIFT+START that row. Those empty pattern could also be used to reset all sorts of modulators (if so desired).

Or is that too cumbersome too?

I personally don’t find that too cumbersome, especially as I already have a row much like this at the very top of my arrangements, where I initialize various things and can safely return to when I need. It’s easy enough to copy them down the arrangement, tweak them if needed, etc.

As far as I understand, row(s) of patterns, with some or all empty, is also a pretty classic tracker thing (complete with debates about which pattern number to standardize on as the empty pattern.)