The wheels on that bike are probably fine. A few years prior to yours (2014), Bontrager had some hubs that couldn't be adjusted and never spun well. If you spin the rear wheel and it stops in 2-3 revolutions, you may have one of those. If it bothers you, then you might look at an upgrade.

Assuming it's fine, get some good tires. I've been very happy with a nice middle of the road offering, 38mm Gravelking SK. Set it up tubeless.

Sure there are lighter tires like the Maxxis Rambler but between durability and ride quality, these are a great balance.