Is it worth getting the new expansion if the highest character I have is level 21? Also on one more topic, is it possible to tell what recipes are in a book before you buy it? Thank you.
Unless you have an 80+ adventurer or crafter, then no, I would hold off on it if you already have all the expansions up through Sentinel's Fate. You can see recipes in a book by right-clicking the icon and examining it; it should have a list of everything in that recipe scroll. :)