Realistically, the data says the AVERAGE National Hospital Capacity in the United States is at roughly 191 persons. For neatness purposes I would recommend 200 beds.
Source:
https://www.ahd.com/state_statistics.html
The math explained:
Staffed beds (746,839) / Hosptials (3909) = 191
There are two approaches to alleviate this concern in my opinion.
OPTION 1:
In the next update, each Hospital Expansion adds x amount of patients per extension.
Pros:
Immediate fix for older players with the proper wait time and credits invested.
Cons:
New players will have to wait a while to get larger Hospital Capacities.
OPTION 2:
In the next update, add expansions to be able to be bought up until 190. So maximum level of 190 since each Hospital starts with a capacity of 10.
Pros:
New and older players can properly invest for the higher bed levels.
Cons:
Not super realistic in some more rural areas, but it will allow players in higher population levels to get the desired Hospital capacity they feel in realistic.
Ranting:
I have seen it posted elsewhere that the Devs wanted to simulate the ER Capacity of a Hospital... That is a cute explanation since you can add the following to your HOSPITAL which implies you have beds and unit(s) for the following:
General Internal
General Surgery
Gynecology
Urology
Traumatology
Nurolology
Nerosurgery
Cardiology
Cardiac Surgery
One would assume that the name "Hospital" stipulates that you have many beds for just one unit and not only 30 beds for a WHOLE Hospital. I know this is a game, but it blows my mind why the capacity was not drastically improved. If it hinders server capacity that's one thing... But if it doesn't, what a shame it wasn't done to begin with!
Listen, I am an EMT in real life and work for a Hospital based EMS service. We are capable of handling in excess of 70+ patients in JUST the Emergency Department.