Combining E-switch and LVP on the same pin is doable, not only in theory but in practice too. I’ve built lights with drivers where I put the E-switch, LVP and OTC on the same pin: Custom dual switch driver finally seeing some light. (driver info is after all photos).
E-switch and LVP on the same pin is something I can continue to stick with, but OTC readings vary a little too much for my liking under voltage sag in FET based lights. That’s why I’m interested in OTSM.
Did that too. I have two UIs that use ramping. The first UI would alternate between ramping mode and boost mode by short off press. A long off press enabled ramping mode where one short off press ramps up, double short off press ramps down. Single short off press stops ramping. Ramping mode times out after a few seconds of inactivity. The second UI was just continuous ramp mode without boost. Short off press ramps up, double off press ramps down, single off press while ramping stops the ramping. I use these two UIs more than normal UIs now days.
In my case it wouldn’t be easier with OTSM, but that’s not what I’m after. I’m after more precis and stable off time measurements.