For me, Uplay started out shitty, and now it is less shitty.
When it first was a thing, I stopped being able to play my games at the maximum setting, anymore, because Uplay was such a resource hog. I have upgraded my computer since then, so it isn't as much of a problem, but my second glaring issue with Uplay was that whilst downloading something, unless I was constantly tabbed into the Uplay downloads tab, the download speed would slowly tick down to 0b/s.
Now, though, it is little more than an inconvenience. Also, what is with those Uplay point things? I get that they unlock stuff in your game, but, like, what is the point?