So, the bottom line is, does anyone happen to have any other suggestions
on how to get the drainage away from the house, over maybe 15 ft of
cement, and not risk having it blocked with ice when the temp drops?
Maybe something with a larger diameter. (I'm thinking the narrow
diameter tubing is more likely to freeze because it fill with water, and
since the ground is fairly level it doesn't have gravity on its side).
Maybe like the flexible downspout extensions, but if so how to attach?
Or am I better off with the gutter thing, since it's open on the top and
even if it freezes, at least the water escapes somewhere? And did I
mention I'm not very handy…

One additional question. Someone was telling me that "everyone" in the
upstate NY area uses some sort of electrical heating wire for gutters
and downspouts, to keep them from freezing, and suggested that might
work for the sump pump drainage tubing. There is an outdoor electrical
outlet close to the sump pump pipe. Thoughts? The one I saw on eBay
looks more expensive and involved ("hard wire") than I want to go, but
maybe someone here knows more about them.