I noticed it when I first visited the shrine, but wasn't sure whether I ought to mention it... Maybe it's just me, but I think the navigation looks
odd in how the links are distributed on two lines, but also how one part of "further info" is at the top while the other is at the bottom. I think it'd look better if the links were split up more evenly over two lines, or at least have the "further" on the second line? Of course, if you like it the way it is or if you've already experimented with it and deemed it not to look good, ignore this. XD
Since you don't elaborate on individual characters on the basic info page, but list the main characters nevertheless, a group image for the reader to visualize what the characters look like may be a nice addition.
I'd also love it if you linked to lyrics of the songs you've provided via videos if you consider that a good idea and not too much of a hassle, but that might really be an individual thing. My approach to music happens via text because it's a) easier for me to visualize the song that way and easier to look at the "content" of a song when you see it in its entirety, b) my English listening comprehension was poor in the beginning. XD (These songs were easy to understand though!) Some people may not have audio available when they browse your shrine, but want to know what the songs you single out are about anyway, so that'd help them too.