A long time ago, three Star Wars books featuring Lando Calrissian were published. They were some of the first licensed Star Wars books ever written. I had often seen them mentioned, but I had never gotten a chance to read them until recently, when a friend loaned them to me.
The books were published in July, October, and December of 1983. The titles were 'Lando Calrissian and the Mindharp of Sharu', 'Lando Calrissian and the Flamewind of Oseon', and 'Lando Calrissian and the Starcave of ThonBaka'. The aithor is L. Neil Smith.
Based on the rapidity with which they were produced, the obscurity of the author, and the titles, you are probably assuming that they were hastily-produced pulp-quality hack jobs. If so, you are right, but that does not change the fact that they were a ton of fun to read.
I'll go ahead and list all the problems first. There are plenty of flaws and anachronisms, things that do not fit in the Star Wars universe. For example, things like bicycles and dinosaurs are mentioned. And despite the fact that the rules of Sabacc are covered in detail, the phrase 'inside straight' is mentioned twice, as if Lando was playing poker.
In fact, aside from the name of the main character and his ship, there is practically no connection to the Star Wars universe. There are none of the aliens or places we know, the technology works slightly differently, and the bad guys are not even Imperials. Lots of strange new aliens, items, and concepts are mentioned that have no place in the Star Wars universe that we know and love. It is entirely possible that the author took some existing plots he was working on and hastily retro-fitted them.
But none of that matters. The books are a joy. They are well-paced sci-fi adventures, with lots of good ideas, characters, settings, and action. They are my favorite kind of science fiction, and they are far superior to a lot of other stuff that has come out with the Star Wars name attached to it.
The author got the character of Lando just right. The character is not a superhuman; he has some skills and a quick wit but is not an action hero at all. He grows and develops over the course of the books.
Lando's droid companion, Vuffi Raa, is another great character, and their interaction helps drive the books. The droid is something of a magic Swiss army knife, but no more so than R2-D2, and it has a backstory to explain its range of powers.
I even like the titles. I've always had a fondness for titles of the form '[Person you know] and the [interesting thing]'. These kinds of titles are a signal of simple fun, and I much prefer that to the kind of short or cryptic titles that are popular nowadays.
A lot of differences between these books and the normal Star Wars universe are not the author's fault. When these books were written, the universe was ill-defined. I've seen some of the old comic books from that period, and they too had a lot of strange, one-off things. And the author did make a good-faith effort to include the Sabacc rules, which were invented by the author of the first Han Solo books.
The main problem is that the overall feel is different from the feel that the Star Wars universe later evolved. The best way to explain this is by referencing the three masters of sci-fi: Asimov, Clarke, and Heinlein. The following explanation is greatly simplified, but it helps explain the science fiction genre.
Asimov's stories are about technology, robots, massive human galactic civilizations, and human social phenomena. Clarke's stories are about strange, powerful, highly advanced aliens, their artifacts, and what happens when different races meet. Heinlein's books focus on rugged individuals fighting things that threaten their lives or the things they value.
Almost all science fiction draws from these three sources of inspiration. For example, the Stargate series is mostly Clarke and Heinlein, with almost no Asimov.
Stories in the Star Wars universe are usually a mix of Asimov and Heinlein, with very little Clarke. The galaxy is basically dominated by a high-tech human civilization, there are almost no encounters with aliens that are very different than humans, and the plots focus on militaristic action heroes fighting for freedom and justice.
These Lando books, by contrast, show a lot of Clarke influence. The plot of the first book is entirely driven by strange artifacts from a super-advanced ancient civilization. The main antagonist is a semi-mystical enigma with access to unexplained powers and technology. The plot of the third book is based on a different set of alien life-forms.
These differences in style, and not any flaws in the writing, are probably the reason why these books, and a lot of other early Star Wars stuff, are not really included in the Expanded Universe canon. It just doesn't fit with the way the franchise evolved.
Now that I think about it, a similar thing happened with Star Trek. The original series had a lot of encounters with powerful and truly alien beings. Most of the modern stuff involves aliens that are at, below, or only slightly above the tech level of the protagonists. That franchise also traded away the Clarke elements in order to gain more Asimov and Heinlein. If you grew up watching the newer series, and then went back and watched an original series episode with hyper-advanced aliens, you would think it odd and out of place even if it was a good episode.