I've been a paying user of EN on PC, Mac, iOS, and Android since 2010. I've got ~27k notes, which is probably still not a lot compared to some of the long-time power users on this forum. I used to use primarily the PC version but switched to the Mac a number of years ago. The PC version was the workhorse. You could do ANYTHING with it, but, it was clunky, and I found that it took more work to get decent results than the simplified Mac got with ease.
By far, the number one improvement the Mac version had over the PC (imho) was the "sort by relevance" column. I could easily find notes by a simple search, without having to make complicated searches on a PC. It was, dare I say it, like Google for my own notes. Part of the beauty of it was that I have taken the vast majority of my books, cut the bindings off, scanned them to OCR'd PDFs, tagged them by author and topic, and put them in EN. So, when I do a search, I got results from inside all those books.
I'm running v10 and v7 side by side. And I've been saying, "man, where did sort by relevance go in v10?!?" Today I discovered...it didn't go anywhere. It's there, but now it SUCKS!!! So, for all of you PC users who are saying "sort by relevance sucks!", I now understand what you're talking about. It absolutely does suck on v10. But, FYI, t is actually a beautiful thing on the v7 Mac version.
This isn't a Mac EN vs PC EN post, btw...but this one thing of the Mac version was actually really good, and somehow they have managed to take a good feature that they "kept" and still break it in the process.