Yeah, get him. He's basically an inferior Kankuro, since his mystery does a ton of damage, but no debuffs.
With poison tai, you get several stacks of poison tho, so there's that. Akamaru's also really god* bulky, so that's a plus. No matter what you do, you'll probably end up eating 1 or 2 of Kiba's mysteries before Akamaru (or Kiba) goes down, which I like better than Kankuro, who I can basically keep useless by killing his puppet with Lightning Assassination Sword as a Lightning main.
He's also the only one you can either get for free, or with minimal spending.