Upgrading Tires and wheels help

I have a 2015 1000xp 4 that have 1300miles and I have burned through my rear tires. I am looking to upgrade all 4 tires to a 14 or 15 size tire. I ride hard packed desert, Sandy washes, dunes and over small to mid-size sharp rocks. Im looking for advice on what tire and size (14 or 15) would work the best and the best beadlocks. Without having to upgrade any suspension or clutch. Thank you in advance for your feedback.