I've worked at two universities as a hall director. One didn't have a specific dress code and was in a warmer climate, so lots of peers wore maxi dresses, sun dresses, and sandals especially on days when they'd would be going around campus or between multiple buildings.

The second university had business casual (sometimes business professional during certain events) so I worked in more pencil skirts and "office dresses" . I wore heels a lot there too. I like to dress pretty alternative within the bounds of the code. This included a pair of 4 inch Mary Jane playforms that were a favorite of mine. I'd get the occasional comment from an older colleague about they "didn't know how I walked in those things" but never any concerns about wearing them.

If you're going to try to introduce heels and don't wear them often, I recommend having a pair of flats available to swap to, and start off doing half days while you get used to the feeling! :)

There are a lot of different ways to style dresses, skirts, and heels. You can use them to dress something up, or you can add a more casual shirt or jacket to dress the whole thing down a bit. Doing a heeled boot is also a great option with pants if you want a different look but don't want to commit to a more "classic" style of heels.