The juice pong table and keg are great, especially since I have them in bars for more variety and kegs are good for house parties as well.
Also, make sure if you happen to have Seasons and a holiday that had school/work off for it doesn't fall on a weekday. It'll be like your sim not going to class and their grade can take a big nose dive. That and if you're rotating between families it's possible for your sims grades to drop as well as their progress doesn't really seem to pause. Had a sim on academic probation due to this. :#
The Research & Debate skill isn't just relevant to just being in university. (Sims do acknowledge each other when they debate in different topics when advancing the skill, so not sure what you mean? Less when they're 'practicing debating' individually.) It acts as a persuasion skill in a way getting into higher levels where you can convince other sims to do things for your sim. Cleaning, taking a bath, cooking meals, and if your sims roommate is thinking about leaving for whatever reason they can convince them to stay. At Lvl 10 you can earn money from debating.
Contributing knowledge can also have your sim earning money (but if you do it too much they can and will die. :*
Robotics have been a pretty fun skill to play with. Works really well with my evil scientist. Feature I've been mostly enjoying is the roommate feature what you can use even if you don't attend university.
Inbetween, it's best to always to ask your professors for your sims class how you're doing which you'll get a progress report form them if you're doing good, terrible or exceeding.