This is my favorite build for leveling...
It's important to note that this build does not work for endgame because TK Wave is only useful as an opener due to its long cast time. I go full balance at endgame as it works for both PvP and PvE, and it is my preferred build for running ops. However, I like this build for leveling because it is AOE heavy, which makes clearing trash mobs easy.
Go up the balance tree first to get force in balance and telekinetic balance (spammable TK throw). Then go up TK tree to get Telekinetic Wave and Psychic Projection. Then finish out with the upper tiers of the balance tree.
This gives you three AOEs: Force in Balance, Telekinetic Wave and Force Quake. Open with TK Wave, follow with FiB and finish with Force Quake if necessary and you can clear almost any group of trash in three moves. For single target, you have Psychic Projection and the bonuses to your DoTs in the balance tree.