I don't like that the expansions are different buildings. I want one large building that can be expanded. Having to start over at a new hospital is exhausting. The first few I tried to decorate and get them all green but it wore me out as you have to start all over and do it again so soon.

Also the expansion shapes are extremely annoying. We don't need 4 doors. One of each side north and south would have been plenty. I would be fine with one door in/out!
It causes you to not be able to build what you need due to funky shapes and extra unneeded doors.

You don't even get to keep your trained staff. One hospital I could not get a surgeon even after years!

I refer the reception desk we had early on. Later on needing a room for it took away precious space we could have used to build something else!

Need better mix of skills when new staff to hire shows up. I don't want to go 5 years without a surgeon again. meh

Janitors are very slow to do things. I hire extra and also the game tells me I have too many yet plants need watering. machines need fixing and trash needs taken care of. The earthquake events apparently gives you lots of trash. I had bins everywhere and some areas had no guests yet I still got loads of trash after that event.

It's not a bad game at all but it could have been so much better with some streamlining. imho