There are times when I wonder if instead of swapping out the regular "main match" rifle for a "Cody Dixon" type rifle, if adding such a thing as a 5th gun could be a viable alternative variation of CAS.
In other words, instead of 10-10-4+, 10-10-5-4+. Ten rounds from pistols, 10 from a pistol caliber repeating rifle (IE a Main Match Rifle) 5 rounds from a rifle caliber repeating rifle, and 4+ from a shotgun. Call it what you will. At minimum, you'd need one more target "a bit farther away" than the "regular" rifle ones. Which means you'd need shooting bays long enough to have said targets added. You could run it as an "experimental" extra category at any otherwise regular shoot to see if anyone would want to try it, or if it was popular.
Along the same lines, have you ever noticed that there are essentially 2 kinds of rifle caliber (By rifle caliber, I mean cartridges that won't fit in a a revolver) cartridges? Type 1 are rounds that would fit in a Winchester 76, 86, Large Frame Lightning, Marlin 1895, or similar rifles. Type 2 rounds are things that would fit in a Winchester 94, Marlin 336, and other comparable rifles. I suppose there is a potential 3rd category that sorta bridges the gap between these two types, and these would be rounds that work in the Winchester 95. Things like .30-40 or .405 Winchester that have more "power" than the things you'll see in the 94, but are very different from what you'll see in an 86. There may even be some overlap in some cartridges, but I don't wanna get lost in the weeds. I've also noticed that the type 1 cartridges tend to have longer long range capability, but that just may be the fact that I'm not the best shot!