RE: i need a little more power
For a little more "oomph" try the following:
Get a battery with one more cell than you presently have. The majority of brushed motors and ESC can handle one more cell safely.
Try different diameter and pitch props.
Try different gear ratios.
Before going and spending all that money, D/L MotoCalc. You can use it free for 30 days. Input the data from your plane into motocalc and then play "what if" to see what will be the best way to do things.