When to go pro?

I have been playing poker for a few years and dedicated myself to sng play for the last 10 months. I really hate my job and envy all you sng pros. I have now played over 2000 sngs and I am a little disapointed with the results, but I feel that I have plugged some leaks and gotten better and my actual results will be better in the future.
Results:
10's:
Played:1,222
Profit: $1563
ROI: 11.6%

20's:
played:788
Profit: $1218
ROI: 7%

Total SnG's played: 2010
Total Profit: $2,781
Total ROI: 9%
Rakeback: $193
Total ROI w/rakeback: 9.6%

My wish is to now move up to the 33's. I would 6 table for 8 hrs a day 5 days a week. If i can maitain even a small 5% ROI plus rakeback I will make around $3,600 a month. That is much more than the $12 an hour I now make at my current job.
I also have 20k in credit limit on credit cards wich would enable me to get by 1st few mnths if things go bad.