Always-on MIDI Capture
Ableton Live 10 Beta adds a new "Capture" feature. This is similar to what FL Studio has had for a bit (and I believe a few other daws have it). Basically, the app is always recording a buffer of midi notes received - even when not "recording" formally. So if you're jamming around on the pads/keys and find a phrase you like, you simply hit "Capture" and it will dump the last X mins to a new pattern (and try to intelligently select a loop region of that).
This is an amazing feature and really let's creative ideas come out with the mental "stress" of being in "record mode". I would definitely love to see this implemented in BM3.