Steve et al,
I know this will sound odd, but after many houses in many climates I found that the best thing to do is just remove the gutters. As in take'em down and paint the soffits.
Then you put lava rock or simlar along the base of the house to deflect the cascading water (the bushes hide it). Make an exception for a few feet of gutter over the entry ways only so guests don't get drenched.
No build-up, no cleaning, no rot behind wet gutters, no erosion thanks to the lava rock (gotta rake it back in place once in a while). No leaves. No splashback into the windows. We have about a 2 foot overhand from the eaves of the roof, and I am not sure how well this would work if you didn't have overhang.
Works for us.