Soloing on a Shaman

[Zyn]

I've been reading through a lot of these Shaman threads and people often say that Shamans are fantastic soloers.

I'm currently a level 21 Barb Shaman, and I swear, my mana costs obliterate my ability to solo efficiently. Root+Rot just kills my mana bar.

Do I need to wait until 24 when I have Canni? Should I consider picking up a poison wind censor and doing a lot more melee?

I have mediocre starting gear, nothing too fancy.

Any advice would be great appreciated?