^another tool to deal with that: don’t forget you can also adjust tempo with Func held down. the change won’t happen till you release it.
also i take it from your answer you know about song mode … jamming in the arranger is a whole new dimension, i’m discovering.
anyway, these are workarounds, per your question … if you want a full-on solution, then as josker says, you may want an OT or some other sequencer.