The ability to limit playback to the area between a pair of brackets, or to anything following a bracket - useful for an intro segment followed by a main segment configured for swiping. At present this can be done by jumping scenes but a bracket option would be simpler. It would also be possible to nest pairs of brackets.
One way to handle the UI would be to add a checkbox to the timeline actions popup
We’ve often gotten the request for named labels on the timeline that could be used instead of a “go to time in timeline,” but I’ve never heard/thought of using this in a in/out form that could be used as a restriction on playback/swiping. Cool idea!
In music it is called a d.s. and coda. The coda tells you where to jump from and the d.s. symbol says where to jump to. Note the symbols used in the illustration.