OK, I will probably go back over some things covered already.
Your GMAT is fine. Applying late and quickly is fine - it depends on who you are and why you are doing whatever. Sure, maybe you can do a bit better if you take your time. I have always been quite happy to admit I got a GMAT book in the summer, opened it in the December, sat it the day before the first of the second round applications was due in. It worked out fine (though the GMAT could have been better, unsurprisingly!).
Applying 3rd round is tough, especially without a wow factor. I know Stern was looking historically low on 3rd round admits this year as yield shifted (to answer some suggestions upthread as it being the easier, which it still may be).
Given the speed of turn-around, I would place a bet your essays weren't as great as they could have been. Otherwise, I would say you should just take the extra year as best you can and re-apply. Earlier.