If all you're ever going to hunt are those same two fields, then it probably doesn't matter WHICH of the two you choose. Coyote rifles tend to have different characteristics than your standard "varmint rifle". Most notably, they're light enough to carry from setup to setup. Leave the heavy-barrel jobs for the prairie poodles and the groundhogs.

My all-time favorite coyote rifle was a Remington 788 in .243. The .243 did cause significant pelt damage (though bullet weights less than 75 gr weren't available then). I use a variety of .223s on coyotes today

If you're just learning, stick to the basics. No need for that gee-golly-whiz rangfinding scope. Especially if you're hunting the same fields all the time, it shouldn't be that difficult to set up some range markers to practice and learn to estimate ranges by sight.