Nothing.
The entry level courses are designed to be exactly that: entry level. They teach only enough skills to make it possible for a diver to plan and execute a simple, shallow dive with a buddy in conditions equal to or better than they were trained in.
If anything, I'd like to see better mastery of the skills that are being taught before adding more skills, i.e., your OW course should have covered both disconnecting a power inflator and freeing yourself from entanglements. Adding more skills to the curriculum before the current skills sets are actually being mastered seems needlessly confusing.
Safety and fun are not compromised by teaching divers only the basics and turning them loose to have a good time. Divers that want to learn more skills have lots of opportunities to do so, those whose aspirations don't exceed an occasional vacation reef dive have no need to learn how to shoot a bag, calculate DOTF or blow bubble rings.