You do need to realize that a flint lock will fire without prime....
Amen! Don't think it won't! I agree, good locks are a must. A mediocre percussion lock will work most of the time, a mediocre flintlock will drive you crazy. Jim Chambers locks are my favorite.
Some old timers loded their flinters with a quilll or feather stuck in the vent hole. This supposedly kept a cone shaped void in the powder charge for faster ignition. Don't know if this works or not. I haven't seen any improvment by doing that. I do use a wooden pick in the vent when stand hunting, especially when the humidity is up. Stick the pick in the vent and close the frizzen, protects it and holds it in place. Simple matter to pull it out and fresh prime when ready to shoot. Definately makes ignition faster and more sure under damp conditions.