I also have an '18 Elantra GT Base 2-liter non-turbo with 6-speed automatic that came with Nexen tires (17x225x45), and they provide a pretty good ride for a 45 tire, they're quiet, and have predictable handling. I had never heard of the brand, but have not complaints.
If you're in the USA, check whether your car has gone in for the recent service recall to update the engine control computer software. It's free. I had it done to my car a couple of months ago, and it made a noticeable difference driveability. The engine/transmission seem to get along better, shifting is significantly smoother, and the awful moaning sound under moderate acceleration is much less noticeable. I haven't put many miles on the car since the update, so can't say if gas mileage has improved. Check it out.