Well yes the main goal is to maximise every participants fun.
A thing that came into my mind is back the days when I played heroes 3 multiplayer there were lots of games with no levitation spell rules in the tittle. Well guess what there were players who does not stick with this rule and the game turned about a massive waste of time. (cosider this for an example)
How better it would be to remove/nerf/limit/optout the spell.
I understand what you are saying. Basicly for an example if you limit the flee capability some players experience will suffer but we must acknowledge that if we don't some others experience will.
I am not stating that this game should have abuseproof levels as an MMO has to have but we should show some efforts to try.
