Hi Mike
Yes, I generally keep the lights on with the vest, unless traffic is very slow.
At the moment the headlight is a 60/55 H4 Halogen, really bright but a big draw.
If in slow town traffic I have to shut either the vest or headlight off. The Eclipse voltage monitor starts to flash low voltage if I leave everything on.
At 50 mph and above the monitor stays steady green or steady amber.
With an LED headlight the vest could be left on in slow traffic and that is with the stock RM23.
With your three phase alternator and LED headlight, you will have power to spare.
You might fit a voltage monitor if you haven't already done so.
Li batteries do not have a lot of storaged power even when fully charged, but as long as the charging system is keeping up, that shouldn't matter.
Glen