On the other hand my feelings about the other two books are much more certain: they suck. Aimed at a readership in the age-range 9+, they make unattractive reading. Three things explain this: firstly, (and even Timothy Zahn has problems with this, which makes me think it is intentional), the dialogue is full of a twee familiarity; secondly, the world is filled with polysyllabically named devices, so you find characters saying "'Han and I will navigate, Chewie,' Princess Leia said. 'I think Han still doesn't believe how well I can fly a Corellian Action VI Transport spaceship. Shall I show him?'" And thirdly, the authors randomly use longer more cumbersome words when they could have used shorter synonyms (such as timepiece for clock, appreciative for thanks, illuminators for lights). Examined closely because of these last two points the books make difficult reading (rating 75 and 76 respectively on a Flesch analysis), about as difficult as adult novels by Mary Gentle, Van Vogt or Gene Wolfe, and 10 points more difficult than one of Robert Heinlein's juveniles aimed at an older, teenage readership.
What all three books have in common is a tendency to appear to be technical, and to work on the appearance. So in Zahn, for example, Princess Leia lands on Honoghr and goes where there is "what appeared to be the food storage/preparation module from a small spaceship". The simple English word for a food storage/preparation module on any kind of ship is galley, but the Princess who is familiar with the handling of a Corellian Action VI Transport spaceship is unfamiliar with such a term apparently. Or is it Zahn's attempts at defamiliarisation that leads him to these convolutions? Most likely it is.
If the universe of STAR WARS is strange enough should it need to be portrayed in this way? In MAD MAX II, Max and his captive, the Autogyro Pilot, walk through the desert; when the picture fades in we know they have been walking and talking for a long time. "Lingerie," says the Pilot. "Do you remember lingerie?" There is the portrayal of another world, no longer anything like our own. The roots of these books are too shallowly sunk in this one.