#1 might make an interesting candidate for selective color, seems very busy otherwise. Maybe don't go full b&w background, just heavily desaturated. The other bike shots lose the strong focal point which was the flag.
I love the last one, just wish there was more context to it like where was she? why is she wearing the hat?
They're very busy (not your fault, crowded area, etc) and the light is harsh (also not your fault, damn that Sun thing..) but I REALLY like #5. I think the background could benefit from having some of the color turned down. It has a great red/white/blue theme in the foreground.
Last one's nice also. Good in black and white too.
EDIT: This is what I meant but I took it a step further and went pretty much full black and white in back. The building looks like it has boarded up windows and it was bugging me. I might have taken them out completely but got lazy.
I shouldn't have brought my 50mm with me, a zoom would have given me more options. The hat she is wearing is my husbands' (her dad) Stetson. He's Cavalry. She was at the demobilization ceremony running around in it.