There have been a few threads offering suggestions for your layout in the past. The space seems to be a bit different dimensions for each one, so maybe these aren’t all for the same room. The location of the room entrance(s) and walls would probably be helpful to help others help you. It might also be helpful to let folks know what didn’t work out from the earlier suggestions to help them focus on your preferences.
10x12 is only slightly smaller than my previous layout, but I could have modeled the same thing, just with the peninsula for the cement plant (which I never got around to anyway). Branch line, mine set in the 50’s, but it’s still used today. Being a branch, it uses older, smaller locos - they don’t run ES44’s up there. I went all the way around the walls, with a liftout by the door.
I am a lifelong Chicagoan, born and raised in the city, now living in the southwest suburbs.
If you are going to build a “Chicagoland” layout, do something to make it look like Chicago. I have seen too many Chicagoland layouts that could be taken for almost anywhere.
Nowadays, there are three types of trains that you see in and around Chicago: freight trains, Amtrak passenger trains and Metra commuter trains. Trains that move around in the Chicago area are almost certain to cross bridges over rivers, so why not include bridges.
In the area just south of downtown Chicago, the most prominent bridges are the PRR lift bridge and the two bascule bridges that on the St. Charles Air Line. Those bridges carry freight trains, Amtrak passenger trains and Metra commuter trains over the South Branch of the Chicago River.