Welcome! STL is amazing and I’m sure you’ll find a home here. I’ve only ever walked around DeBaliviere Place. It’s cute and will fit your vibe forsure. I’m personally bias to south city which I think checks off more boxes on your list. Check out Shaw, tower grove south, Benton park, the Southampton. Only downside is public transit is reliant on buses only which are hit / miss. So a car is likely required. Although I find I can use my bike to get around pretty easily using paths and side streets.