I'll wait a good week before saying anything in the OT about it.
Leon is meant to have a sexual infatuation with Chuck Greene. If you watch when Chuck first rides into the elevator in TIR at the beginning of the game Leon is checking Chuck out and then turns away when Chuck looks over at him. In his boss intro he throws the keys to the bike away from Chuck so he has to walk over to them and bend over to pick them up.
I believe the model of Leon is a modified version of the original Chuck Greene model from early production. His face is also used again as one of the militia men on the rooftop (the one that doesn't talk in the cinematic)
Other stuff that is pretty subtle. Chuck never drinks coffee in the cinematics until he discovers the truth in
The scene where he is framed for the outbreak he is about to sip and doesn't and then when the explosion goes off that signals the robbery he doesn't either.
Really minor stuff...in The Boykin intro when Rebecca yells out for Chuck it is actually Stacey's voice. We never had a cut of the actress for Rebecca yelling out his name. I think it is the same sample as in Ending B.