What I was saying with the planning is that you can plan some outings that require advance reservations and stuff. Just leave room for the "spur of the moment" things that he likes to take on. Let him "lead" during those times. That was also a thing you mentioned before that bothered you, that you were leading him through everything, so here's your chance to give him his turn.
About the other guy: if BF didn't know that this was the guy that was hitting on you before, maybe he didn't see him as an immediate threat, especially with him there in the same place. He also may have been observing from a distance?
