As much as i love black powder and the older guns of yesteryear...i just cant go flintlock. Not that i dont like it...i just dont see myself having the dicipline and know how to get a spark every time. I know some guys are able to get them to shoot just as reliably as a cap lock gun and with no hangfire...i just feel overly intimidated by them. But to be able to keep shooting over and over with flints you knapped yourself would be an amazing feeling of accomplishment, especially if you made your own powder and cast your own projectiles.
If black powder is the dark side, then flintlocks is the black hole in space. Here's what I think. Unless you have a high quality lock, the flintlock can be "frustrating". The locks that came on the TC's, Traditions, the Lymans, etc. were not "great" locks. That has convinced many that "we all do" get the occasional failure to fire.
I would argue that with a high quality lock, and rifle/barrel/vent, that just is not true. I have an expensive Jeager, and it never fails to fire. Ever. Never has. My Brown Bess was not an expensive gun (at the time I bought it) but the lock, being a copy of a tried and true lock, goes bang every time. Now the mainspring on the Bess was a bit weak when I got it, so I won't say it's never failed to go bang. But I can count the times....that would be...two. Once when just working up loads, and I'd fired it many time, and it was getting really dirty. The other time was at an Appleseed shoot, and we were opening the shoot/ceremonies by shooting a Redcoat target with the Bess. About 100 people watching. You could hear a pin drop. I pulls the trigger. CLICK. No sparks. I quickly re-cocked the gun, shut the pan, and BOOM!
When a flintlock gets dirty, from shooting on the range, target practice, yes even the my Jeager "could" !! fail to fire. But a clean gun, loaded right, cleaned right, will always go off. If it doesn't, the odds were about the same as your .30-06 not going off. Ever have failures to fire with a cartridge gun? I have, many times.
So to be really happy with a flintlock, you have to put out some bucks. $$$ And, you have to learn the voodoo and magic. Not saying that some of the moderately priced flinters won't work well, some guys get them to work. But that never misfire, always-goes-off thing usually comes at a price. The safest bet, short of buying a custom made rifle, would be to get one of the reproduction muskets. They have locks copied from the originals, and will be very reliable. The other solution would be to get a rifle that Davis or someone makes "improved" locks for.
Okay, just a thought. I could be wrong!
O.P., I think these guys will steer you in the right direction. That Renegade is a nice looking gun. My only advice would be to sand/strip off that horrible (no offense) factory finish, and give it some stain and a nice oil finish. !!