I don't think the first book should take more than 10 eps, that would be drawing it out.
However, I disagree that the SF mini that was done left out too much. Yes, stuff was left out, but was it important? Depends on your POV. If you go from the "what do you need to know to understand the story" POV, then no. Unlike the film which took some large liberties with the source material to work around problems, the mini did it without deviating so much, mostly by omitting. The Irulan part was altered, but I think that was to give the chance to have more scenes with the Emperor to get info from that side. Lynch's solution was "have the Navigator make Jose Ferrer give a plot summary monologue", which in retrospect is a bit too on the nose as "mandatory exposition scene".
Lots of the details in the book are unnecessary when the story is told in a visual medium. CHOAM is almost an afterthought in the books, it really isn't needed at all.
The Jedi Master
Yeah the navigator was a giant fish/man mutant Deus Ex Machina for a whole lot of stuff they couldn't fit into the movie. I loved the books of Dune and Starship Troopers. I also loved both the movie and mini of Dune. While I liked the Starship Troopers movie I view it as being within the ST universe but something altogether different.
I agree with Kryptonite on cutting movies based off books some slack because there will be some artistic/directorial license, but that doesn't keep a part of me wishing that it was truer to the book.