I think tags could end up needing a lot of space, at which point Tiles mode may be a better fit. That lets you choose which information is displayed next to thumbnails, and lets you have more room to place it.
Tiles would also give more control over exactly which date field(s) is/are displayed. Might be worth a try.
For the rating, there's an option to overlay ratings on thumbnails. It's only for display and won't let you edit them, but something like Star Ratings Buttons/Menu should take care of that and streamline the workflow. (In-place editing would definitely make sense in the future, though. I'll add it to the ideas list.)