Get rid of target locking, institute "sticky-targeting", triple the combat range, and reduce the amount of buffs and debuffs so my hand doesn't tie itself into a knot when I try to launch some abilities and move at the same time.

I'd also make LMB your default attack, RMB heavy strike, and make a catch all "melee strike" ability that is divorced from the weapon itself (though it would still obviously use your ranged weapon if you had it equipped).