@Ferrum1
I've found that it really is hit-or-miss depending on the skills of the author.
Like you, I pretty much automatically turn away from any story that the author thinks needs a huge cast list or dictionary. I'm not going to bother trying to keep all those characters and words straight in the brain.
For an example, in Three Square Meals, I think the author is just at the borderline of good in terms of the number of "species" involved. He does a great job of illustrating the species each time they appear so you don't forget that Maliri are blue-skinned hotties and the Khintark are the ugly bad guys.
Because he does such a good job of working the description of the species into the story, you get a constant reminder of what they look/act like and don't feel like you have to keep them straight in your imagination. Same goes for his use of alien language.
I'll keep that in mind in the future, especially as I revise my current story (currently in development) as it features a bunch of different species, using a LOT of specific foreign words and phrases. Typically, authors WANT to avoid repetition, but in this case, constantly repeating the same thing serves a definite purpose, making establishing clear lines more difficult.
In my case, I think I'm clear, since most of the terms and phrases consist of variations of either "Hey, You!" or "Screw You!" in various languages, but I've already started restating what specific terms means, each time they're used (specifically, the names of the different species/races).
As for cast lists, I prefer complex multi-character dialogues, as I tend to write more far-encroaching epics, but I also include cast lists (and limit them) to make them both usable and easy to reference. I'd rather not limit how far a story can range, but I also don't want to overwhelm readers.
In all, it's a fascinating dilemma that all authors should be aware of. If you don't need an answer now, it doesn't mean you won't some time in the future.