Tanking- -Unlimited OA's per turns. (but still only 1 per provoke) -Make any spell or ranged attack provoke OA's. -Get rid of Opportunist talent, allow OA's to be done by anyone holding a melee weapon (except a staff). -Give Man at Arms a 0 ap power to "Mark" a target within melee range. A marked enemy has a penalty to hit anything but the man at arms, and when it tries to hit anything else, it provokes OA's.
AP loss from movement- -Separate AP pools for movement and actions. Speed sets your movement AP, Con sets your action AP. -Create new skills that take movement AP: Disengage (move away without provoking), Power through (ignore terrain effects). Stealth could be put here too.
Cooldown imabalance- -Allow STR and DEX to reduce cooldowns of MaA, Scoundrel and Marksman. Duh. -Double or triple the cooldown timers for summoning spells. No more disposable permatanks.