I wouldn’t stress about locking yourself to a class. Leveling is fast, and nobody is limiting you aside from your own schedule (or desire to only have 1 active character).
From past expansions, I’d say it is a lot of buttons compared to the stereotypical 3 button rotation class, but nothing overwhelming. You are not dealing with 16 totems like vanilla days.
Imo, make 1, see how you like the playstyle, and go from there. Or a trial character to get the 70 feel asap.