Congratulations on your new tractor, I think that you will find that tiller will make your life a lot easier. They will do so much more work than a walk behind, my garden prep went from at least a week down to just a couple of hours. I can wade through waist deep annual rye cover crop that would turn my troy built tiller into a ball of stalks in about ten seconds flat without finding anything on the tines when I am done.
Welcome to the forum from another western WA resident.