Changing the diameter of your tires does matter, even one inch. If you go larger you are effectively lowering the rear end ratio and losing power.
Tread design has improved a lot in the last ten years. Consider the type of driving you do. It is mostly on the highway and gravel roads, then you need a less aggressive tread. There are plenty of all-terrain tires that are quiet and perform well in rain and snow. You don't need Cepek mud tires with loud aggressive tread unless you are pounding the bush all the time.
