Restore elemental resistances to the game, and Add in Ice, Lightning and Fire attacks for mages, warriors and rangers. Fire gives a chance for burning damage, Lightning for stuns, and Ice for slowing. Those effects could also be used against the player. Chilling effects might make the choice of a fast or slow weapon a more serious debate.
Summons are okay, but increase the amount of summons you can have at one time, or failing that, make that a property of putting points into Summon Mastery. Summon Mastery should also add a percentage to the HP of summons (10% per level)
Healing could scale better with level. It's really great when you first get it, but it drops off in effectiveness quickly. At rank 15 it heals what, 300 HP? That's only 1/4 of what a high level character can have.
Fireball has a problem - the cooldown is too long. Additional points should gradually lower the cooldown. Right now, the mage only has one attack spell it can use at will.
Skills should not punish the player for using them. So Charm should not reduce the amount of XP a monster gives the player, like it does currently.
Jump Attack is a neat idea, but the problem is that it only works with the one attack, and doing one attack over and over again is not that exciting to watch. If you don't do Jump Attack all the time, those points are wasted.
Ranger Surprise It's an arrow skill which reduces enemy resistance to melee attacks by 25 more points more than it does to ranged attacks! EDIT: You could replace this with an Ice Arrow skill which does zero damage, but slows the enemy's movement and attack for several seconds.
Encumbrance Ditch this skill and let us put things in containers again.
Stun Arrows the cooldown is too long for the length of the duration, given the numbers of enemies you face at once. You can take one enemy out for a second or two, but the cooldown makes it useless in a fight with multiple enemies after the first shot.
Reflect isn't that great because it deals damage to the enemy based on the damage that the enemy inflicts on you. The problem is that the enemy has incredibly high HP, but doesn't deal a lot of damage to you, so that 20% reflect damage at Rank 1 isn't that impressive. Reflect Rank 1 should start at 100% damage back, and increase, maybe by 10% per level?. Boss enemies could have resistance or damage reduction to Reflect attacks if that's needed.
Defensive buffs Are all simply inferior to offensive buffs, they're not that effective at helping you stay alive compared to wiping out the enemy faster with offensive buffs.
