As much as I like Frank Herbert, and enjoy almost every Dune book, the House series of Prequels were better than Herberts books after Children of Dune.
Absolutely not. God Emperor of Dune
is an intellectual piece of science-fiction literature by a highly articulate, skilled writer that was pushing the genre as far as it could go.
The prequels are pulpy, throwaway Star Wars
action novels. I commend Christopher Tolkien and the Tolkien Estate for resisting the temptation to licence out Middle Earth to other writers. You just end up with a diluted legacy from hack writers looking to score a quick buck.
I'm a HUGE fan of the star wars novels (not every one obviously, but as a whole I love the star wars EU) so comparing the House books to SW novels is a compliment in my opinion. Kevin Anderson has written some great SW novels. As much as I love the Dune series, I could literally think of a ridiculous number of SW books I enjoyed more than God Emperor. Again, God Emperor, Heretics and Chapterhouse aren't bad (neither are the last two books in the series by Herbert/KA). But, they aren't close to the quality of the original 3 Dune books, and I liked the House prequels better, too. God Emperor, from what I can remember, just got ridiculous. It starred a whole bunch of characters you don't care about (and, because of the time jump after it, never see or here from again). Leto and Duncan are the only familiar characters, and I honestly can't remember anyone elses names from that book. I think there was a woman who had atredies blood and was a main character.
I also remember Leto getting killed, and then actually not totally dying because his mind was split into all the pieces of himself that seperated from his comical human/sandworm body. After GE, there is a time jump that leads to better books than GE, with some characters that are atleast somewhat memorable and a better plot than "Its about time for us to kill Emperoor Leto, right?". I know I'm sounding negative about GE, but I do like it. Its just my least favorite Dune book, and I can think of numerous other books that are much better than it.
As for the Tolkien stuff, that was definately a series that only needed 4 books. I'm glad its never been liscensed for new stuff (although, honestly, Peter Jackson's Hobbit is so loose an adaptation of the book it almost counts as a seperate version of the events in Tolien's book). That said, the LOTR stuff thats not Hobbit or the trilogy is pretty bad. Well, not bas so much as incomprehensible. I actually would love to see a good writer turn the Silmarillion and the other stuff into actual stories/novels that read like books. Right now, I've been defeated by the Silmarillion twice after about 70 pages. I can read complicated stuff, and I really enjoy reading. But, The Silmarillion is basically unreadable. I'm sure there is a good story in there somewhere, but it needs someone to turn it into an actual book. Besides that, the LOTR series has been left alone when it comes to books, and I think that was a good idea. The Dune series, though, is a totally different situation, and I think its only benefitted from having more books.