I haven't read any good Robin Hood books. I tried one by Parke Godwin, but got very annoyed at his inconsistency.
The ones by Cornwell are very good. They're more historical novels with a little magic thrown in. Much more action oriented than Stewart, who used Merlin as the protagonist. Merlin in Cornwell's books is very different and a lot of fun. That describes most everything in this series, though. It's all different but fun. It's not typical Arthuriana.
But then, what is? T.H. White's Once and Future King is also very good, and a good overview, but he makes Uther Pendragon (Arthur's father) William the Conquerer, so you have a Norman Arthur instead of a Britonic one, and sets it up for culture conflicts between the celts, britons, saxons, and normans. Very interesting, but not typical. It's still very much works for the generic medieval Arthur. It's a very nice interpretation of Mallory when all is said and done, and with a much smoother writing style.
Mallory's Le Morte d'Arthur is, by the way, sort of the canonic Arthur, if there is one. It's quite long, though, and with a definite Medieval style. This is difficult for many people, and I don't blame them, though I like it.
Then there's Peter David's Knight Life, when Arthur comes back to run for Mayor of New York City. Well written, but well, not much else needs to be said besides "but." It's kind of fluffy. Not as good as Mark Twain's Connecticut Yankee... but definitely of the same ilk.
I don't like Mary Zimmerman Bradley. She has brilliant ideas, though the feminism is a bit heavy handed and not alway directed. But her characters and dialog are awful, imo. This one is more political, like Stewart's is. I throw it out in case you want to try it, but don't consider this a recommendation.
There's also Tennyson's Idylls of the King. A fairly safe interpretation, but that's maybe my looking back on it with a lot of Arthurian background. Plus, the style... well, it's Tennyson. It's a great work. But not exactly the easiest reading.
I know you asked about reading, but go see Excalibur. A great interpretation with wonderful filmmaking. The music is from an opera (I forget the composer) which was also about Arthur.
There's a ton of stuff that is Arthurian in theme, but not necessarily in content. Like the Robin William film The Fisher King, or the series The Dark is Rising but I'm assuming you want the actual legend. There are also a lot of bits and pieces, like many of Marie de France's lays.
The question is, do you want legend or do you want writing style more? If the former, go read Malory. If the latter, Tennyson and White. If you want just a good Arthur story, Cornwell. If you want his application is unconventional ways, Twain and David. Those are my calls.
