It is very possible to get your ROI to around 10-15% in the $22s, but 5% is still good. With that said, with a 1k game sample it is very possible for your actual ROI to be a few points higher or lower depending on the variance. Your bankroll should be big enough to play the $30s, but just make sure that you move back down if things don't start out well. Also be sure to keep studying the game and not get stuck brainlessly grinding.

Cheked your SS stats, last 500 games at 10% ROI, it's a solid, since you are playing 2 tables. It looks like you're improved your play.
I think there is no big gap between 22s and 33s, either bankroll requirements or skill of opponents. So you can try 33s, maybe start from 1 table to see how it will be.

I agree with WBR and xSCWx. 
And you don't need 100 buyins to take a little shot.  There's nothing wrong with pushing yourself a little now, you'll be rewarded in many ways when you encounter tougher competition moving up in the higher stakes games down the line.