I bike in the PNW and have gone through quite a few rims, all from brake wear. The OP is correct. If you use brakes equally, the rear rim wears out first. I believe that's because the front wheel throws up grit, even with a fender and flap, and the rear rim picks it up. So I started using the front brake more than the rear, but then all that happens is you wear them both out. Whoop-de-do.

The solution is extremely simple: have the rims replaced with Open Pro Ceramic rims. This not the same as Open Pro CD! The OP will have to have the LBS special order the rims, and they will cost more than a normal Open Pro. I usually pay $90-$100 for just the rim. However, they just don't wear out. As far as I can tell, it's a permanent fix. I advise switching to the Koolstop green pads that are meant for ceramic rims. You can use black pads, but they wear out quicker. You'll go through the first set of pads pretty quickly, but then pad wear is more normal.

If the shop does a good job of building the wheels, they will last for many years, even in the PNW.