I think you're seriously under-estimating the finishers.
Monk can be as active as you want OP, and you'll probably start with a few limited cycles and then expand as you get better at cycling them. One handy trick for newer players is to figure out for the encounter ahead what your most common strikes will be, then remap those to the same limited keys but keep your generic finisher. You can do that and (for instance) set up a portal-set for Shroud pt 1, then when you get to pt4/5 switch to a boss set. You can have a set you use in epics, etc.