Ditto. In addition to increasing your odds at a great outcome, with a few months to focus on LSAT prep you will also increase your chances of a really nice merit scholarship, tax free.
Sorry, there are no good reasons to NOT take a gap year, but thousands of ($) reasons to take one. Now, if you come from a wealthy family, maybe that does not matter to you, but even so, why not give yourself the best chance to earn a huuuuuge discount each and every year? A tax-free merit scholly will be the easiest money that you will ever earn.