I've got one tree next to my house that drops spiky green golf balls, which do a wonderful job of plugging the downspouts almost instantly.
Those damn "spiky green golf balls" are an issue for me, as well. However, they're the least of my worries. I just have too many leaves, seeds, and blossoms. I haven't found any of the "magic" fixes that actually work. Over my gutters, I have a Pine tree, several Maple trees, a Gum tree, the spiky green golf ball tree (another species of Gum, I think - the neighbor's), and at least a half-dozen Aspens. In my yard, or the neighbors', there are massive Cottonwood trees (unending nightmares), various Oaks, a plethora of Apple trees (the blossoms are a nightmare), Cherry trees, Peach trees, Plum trees, more Maples, and several dozen Aspens. It all adds up to so many leaves, no man can keep up - even with gutter covers (helmets, screens, foam inserts, whatever).
*(I'm not sure if the Cottonwoods back east are as bad as the west coast species. If you're not familiar with the seed nightmare, let me know. I can explain.)