personally, on my 20 monk i use 4-5 buttons, im a dark monk all my other buttons i can hit outside of a fight and be just fine XD
1=air strike (im a wind monk)
2= flame strike (i picked up some fire stance so on bosses i can use that for + dmg, + to hit, and + ki gen so i can hit button 4 more)
3=stunning fist (no matter what stance/path you choose it is helpfull like really helpfull)
4=Touch of Death, personally i think its one of the best ones i have
5=weakness to (whichever sorc there is, if no sorcs then i put finishing move on and after 3 tods i hit it and hope that the boss doesnt save so i get to hit him for 750 or 375 with tod instead of 500 or 250)
outside of combat i choose wind stance or fire stance (90% its wind)
i choose which handwraps to use for the fight/dungeon
when im fleeing a fight i hit my fade so that way i get 1 min invis and 15%(or was it 25%) incorp, if i start to take dmg a lot i just click it
dark monks=little button smashing, but thats just me, because i dont use things like sunder/trip stunning blow (would if i had it, but forgot to grab it somehow and dont have money to redo feat)
on my light monk/acrobat (one of my favorate chars)i constantly switch between fire punch light punch fire punch combo (once a min) and lightX3 combo (love the heals) i use fire stance (if its not obvious why then try an acrobat/monk) and when someone activates that trap before its disabled i hit wind stance to get it done easier
ya i might be the minority, i might not be, all i know is dark monk you dont need the combo's AS much (i hear that the fire/dark/fire was improved greatly so i might start using that, and i always fealt void strike as a waste...)