It's kind of funny how civilized this has become here after all the "Curse su*** so bad" in the other threads but I love it, let's have this talk here!
First of all I have to say I really kind of like Curse, I find the repository quite extensive and the response time nice and fast. I always like to filter for the newest version and then sort by added most recently to see which of my favourites have upgraded already.
But I'll reiterate the two major points that have already been said here:
A "hot and trending" category per month and/or week is absolutely warranted. I do not agree that the "newest" is sufficient for that. That list will always be too verbose. And in the popularity of all time MechJeb will never be conquered
The UI does feel a bit cluttered and it does not really look very modern
Honestly, my major criticism of Curse is something they can't do anything about, it's that almost no mod has an extensive description filled in there... But that's totally understandable, clicking through to the forum is always an option