Wheels make a huge difference, best place to save weight.
Yeah right. 200g is ~0.25% difference in your total weight - it is generally accepted that a human can't detect differences smaller than 5%. The difference you're feeling is placebo. Oh, and what's more if you're feeling the difference on a climb then it makes no difference whether you save 200g on your wheels, on your frame, on your shoes or on your gut.
OK so I have a (very) light bike, but I'm not a hypocrite because I accept it doesn't really make any difference when riding (I used to do lots of races involving carrying the bike, in which case bike weight does make rather more difference).
I'm surprised at the problems you have with Tune hubs - mine are over 6 years old, have been ridden in all conditions and I've never touched them. I'd certainly rate them as requiring less maintenance than DT240, which is what I have on my spare set of wheels (used to be my main wheels) and needed a couple of bearing changes over the same period. Maybe King/Kong are a little less delicate than Prince/Princess.