After listing over 15 things wrong with the new site, I figured "feedback" should also include the things you're doing right. If nothing else, it will serve as a "pep talk" and add my vote to keep doing these things. The following is just my opinion, of course.
1 - Stacks. Much better than the old collection, especially for people like me who already had over 300 games in the collection, which forced me to filter things if I wanted to find something. Stacks (once they work right) are definitely something I'd like to see kept on the site, and improved upon (filters, sorting, etc).
2 - Visual design (not to be confused with layout, which does have some issues yet). This is subjective, for the most part, but I like the fact everything looks more modern. As long as it doesn't get in the way of functionality (the layout issues mentioned before), then this is a step in the right direction, and kudos to the people who designed it.
3 - Video player. Other than the fact we still can't watch older videos, it's overall a better player. I like the option to stretch the screen to fill the browser, without actually having to go full screen.
I suspect, as things in my "negative" thread get addressed, this list will also expand.