1

It is possible to add (define) to stopwatch key combination to start / stop stopwatch?
In present solution I always need to click RMB to start / stop stopwatch - using key combination will be much faster.

2

I'm looking into this.

I think the only gotchas are that 1. we can have several stopwatches visible at the same time. This shortcut will send the event to all of them. And 2. a stopwatch may already have data, we need to handle this gracefully. There is also a new stopwatch with multiple time sections and split times.

3

OK I made a number of tests and for now my conclusion is that it's better to not try to rewrite the existing times.
In the case of the multi-time tool the "start/stop" combo command is always ambiguous anyway, but I think it's more important to have this combined start/stop shortcut for ease of use and parallel with a physical chronometer rather than separate start and stop commands.

So basically if you just add a new stopwatch object it will work just like a physical stopwatch (one shortcut for start/stop and one for split). And if there is already some data, it will only "extend" it, stopping the last live section or creating new ones at the end.

If you miss something during the live tagging you can always come back and change the end points manually with the menus.