My take on it is that we should include *-desktop-full, and instructions for how to add more; if you want a specific extra set of packages for your class, then add them to the drives (following our instructions) before you hand them out to the students. I don't think we can second-guess what people will want, given the range of possible users.
I agree that the Turtlebots and Parrot drones are popular. However, to me, the Turtles are in scope and the Parrots are out of scope (for now). I think that it all comes back to use cases, again. Who are we aiming at? Are we aiming at students who will be likely to be using turtles (yes, in my case). Are we aiming at students who are aiming to use Parrots (no, in my case). Of course, my use case is not your use case. I can see the drives being bundles with the Turtles, but there's an equally-strong argument for bundling them with Parrots, too.
I also see the drives as being self-contained for the first three weeks of class. Everything you need to do to get through the tutorials and get some simple simulated robots working. Perhaps to get some simple things working on real robots. After that, then I think that the variation from user to user (class to class) will be huge, and wonder if the best we can do is to come up with guidelines to build your own USB drive. Or, perhaps there's a market here for bespoke USB drives (tell me what you need, and I'll deliver 100 drives to your door by the end of the week).
-- Bill