I'm not completely down with the notion of eave troughs. They fill with leaves, they rust, they fall down - there's got to be a better way. Why do you want them in the first place? Well, I can see not wanting sheets of water over exit doors (nor icicles), and maybe you wouldn't be able to see out of windows or tell how much it's raining if sheets of water were flowing off the roof. There's one more purpose - you don't want water soaking in under your house, which could affect the foundation - settling, cracking, leaky basement. But the water around the house foundation would be better served by creating a dry, perhaps concrete, "moat" around the house - collect all the water and run it to a distant low point. As for doors and windows, simply have open-ended gutters above them that drain to the sides and into the moat below. No need for downpipes even unless wind blowing the water is an issue, then you could angle the trough and run it down one side. OK, by the time you put downpipes on every window, you'd equal the amount of trough to run around the eaves. But would you really need a downpipe for every window?
