That's a very good point. I have been thinking on this one for a while as well.
Originally, I intented to use the study for this.
In this room you will be able to assign a teacher and student.
The student will get substantial experience in the skill the teacher picks.
So this will be one way to catch up and feels like it fits the overall theme (not to mention some great girl-on-girl opportunity
).
That's the solution I like most so far.
Another thing that I have considered is having staff members that join at a later stage in the game have a higher level, but I'm not sure about this one yet.
Finally, I have thought about tweaking the skill level impact in such a way that it doesn't necessarily mean you fail at a lower level (except for the most demanding guests), but that feels a bit like a waste.
It might be a combination of any of these, or just the study, as I prefer that one and it is the easiest one to tweak/balance.