17.5 in wheels and tires

Our trailer weight is just less than 15,000 pounds. We have about 25,000 miles on our G614’s. I ran a year with 90psi in the tires and have some wear on the outer edges, the wear appears to have stopped after going to 110psi. I’m also planning to replace the tires this summer. Based on the weight of our trailer should I stick with the G614’s or should I move to 17.5 rims and tires? We put 8-10 miles on a year.

Thanks