Too lazy to go through another "detailed" thingy so I will keep this short and simple.
Rage was a pretty useful skill. When paired with guild rage, the player gained 40% more damage. Removing the skill screwed players over.
Energy is plain out poop. Takes a few minutes to build up for about 1 minute ( I think higher level means more time ? Damage bonus nice though ) of a damage boost. It can only be used every 5 minutes, making it even more useless. Pretty much, the whole point of the skill is for a player to collect heropedia enemies.