Personally, Faure is lovely- his requiem is a good one to try if you’re already enjoying Mozart. If you wanted to try some opera, I would suggest Puccini’s Madame Butterfly. It’s utterly beautiful.

Classic FM do a hall of fame every year where the public vote for their top 200 songs so it’s very mixed in terms of composers, instruments, it even had game and movie music in it. If you’re just getting started, give that a go because it will show you a bit of everything! Have fun