IMO, NO.

There is very little to none difference between a good gmat score (like 730) and a distinguishing one (like 780 for instance). I am quite sure it won't help you further even if you get 780. On the contrary. Seeing you got 730 and then retook the GMAT is kind of weird (unless you mentioned in your essays for instance that you are always striving for perfection or some sh*t like that, which kind of explains why you might do this but anyway it's not worth it) for your application and this might hurt you.

You should only retake if higher gmat score complements some other part of your application VERY WELL. Even with average GPA your 730 covers your academic ability pretty well. Actually I can't even think of a situation where you might benefit from a retake with that score, unless you get 800, although it's still not clear if 800 will help further