That was the first thing I changed on my TJ. The PO had 33" E rated Toyo MTs on 17" rims. Those tires were so loud and the ride was pretty awful. I found a set of TJ MOABs on CL and got 32" Duratracs. Big difference in ride quality and noise level. You'll like those KO2s. I hope the 50-60 vibes go away with your new tires.
If they do, I could almost live with the 65+, almost. I also took advantage of some free shipping and ordered the last 2 rear lower arms which will complete my control arms selection. I don't expect this addition to change anything in the vibe department.