hmm... how far back were your bindings? and yeah if you have a bigger boot you obviously have less ski front and back, but it doesnt mean you need new skis. if your comfortable with what you have, then keep the skis and the mount. no need to fuck your shit up because your tails seem small.
BUT, i would personally recommend a center mount, on a longer ski, something in the 177-181 range, assuming you weigh around 175 or so. but if you ride more park, then theres no need for a center mount. that shit is more for all mountain skiers, such as muah. so do what you think you need to do.