My Current Skill Build (Level 30):

1-stomp (Just for the taunt)
1-singularity (For the knockdown)
6-vigor (I do not have money for stim)
6-increase mass (Useful for tanking)
6-growing rage (Great damage esp since im using cannon)
5-gravity well (crowd control)
5-graviton slam (good damage)

This build is largely for tanking and AoE damage without the usage of stims. I normally buff with increase mass, vigor and growing rage before enter into mobs and it increase my survivability until I finish them off. The rest of the skills are very AoE based, mainly to take on large mobs and maintain aggro. Im thinking of switching graviton slam for backbreaker as it does huge amount of damage when used at the right moment, but doing so will reduce my ability to take on large mobs. Need some opinions on my build and how can I improve from here.