I'm starting to see the casing on my rear tire. Currently riding the X'plorer Ush. I probably have 2,000-2,500 miles on them.

First off what do people generally do? Do you push the front to the back, the front still has some life, and just buy a new front? Or do you replace both? Or just replace the rear I am in tubes, but might go tubeless next round.

Also what are good slickish replacements? My gravel roads midwestern limestone and not that course. I have heard the G-Ones are good and fast but have a short lifespan. The compass are fast but not very durable. Gravel kings look like an option.

Most of my rides are about 75/25 gravel and pavement but sometimes 100% pavement. I'm not winning anything so I'm willing to take a bit more rolling resistance for durability. Keeping with the Ush is tempting but want to get other people's opinions. Finally, is there a huge difference between 35 and 40 wides? I couldn't go much wider.