Hi brownman777,
First off, a 710 is a good score and since you have said that you have improved you profile, it might be sufficient to get you into a to B-School.
However, if you have set a target of 750 for yourself, then you should go for it.
You should opt for a score guarantee course. Obviously you would not want your money back, but a guarantee shows the confidence of a company in its course. You can find the details of our course and take a free trial too.
Since you have not been in touch with GMAT, I would recommend you to take a mock CAT ad post your scores here. Post which, we can take it up.