inquisitor is not a roleplaying game, its a narratve wargame. you can adapt its rules for a roleplaying game (ive tried it before, and it doesnt work - too complex, combats are nightmares) but that doesnt make it a roleplaying game.
ive seen many a party in real roleplaying games desintegrate because of frenzied barbarians, red wizards and shifter paragons (no prizes for guessing my RPG of choce
) things have to be as close to fair as possible (or you have to have nice players) or someonell end up getting hurt.
a good GM HAS to restrict, otherwise things will spiral wildly out of control, its in every GM guide there is, of which i have many. Of course this has to be within reason and with good explanations given. The most important thing in a roleplaying game is that people have fun and if one character is pissing all the other players off becasue of his uberpowerfulness (that would be a marine in =][=) then the game is not living up to its promise.