Cities: Skylines - Campus Review (Delta_Four_Niner)
This is a cautious recommendation, with a caveat to wait for a Steam sale.
Campus is a big DLC brimming with new assets and the freedom to design a university campus to your heart's content. In an amusing twist of fate, back when this update was released I had searched the community hub for college buildings to mod in-game for beautification. So this DLC seemed to be exactly what I was looking for. The three different school tracks it offers provide a wide-array of options for how your university can look, with a fair bit of customization and freedom of layout. On the surface, it comes with base game functionality that contributes to the city.
That said, it is definitely a late game mechanic that works better with a larger city and a bigger profit margin. The assets do not come cheap and can easily drain a city's funds unexpectedly if you don't watch your spending. Also, at times there are hardly any students attending due to in-game mechanics regarding population statistics. In essence, your beautiful campus can sit empty. As far as functionality goes, Industries and Parklife do far more for your city design than this DLC pack will.
But as far as having beautiful buildings to plop and freedom for artistic design, Campus still offers a lot and I've enjoyed it.