Most folks want the nostalgia back, their first rocket, etc. Hence the 3FNC's on the list. I'm pretty lucky, I grew up on Centuri, and the wonderful folks at Semroc have been doing a bang up job of bringing back many of my fav's.
The ones that I's like to see that are not being made by anyone:
The Centuri Fighter Fleet series, (F104, F15, Mirageetc). My first rocket ever was an F15. Those were sooooo coool.
Buck Rogers kits
(Jeez, I think I have a thing for the fiberboard kits):eyeroll:
Scramjet
How about the entire 1977 Centuri catalog.
Make the following Pro Series II:
Colonial Viper
Space Shuttle (the whole stack, not the one that was just the orbiter), Both the NASA proper and the Centuri one
Fatboy, like Estes did with the Der Red Max.
Jayhawk (bigger than the Magnum D)
Buck Rogers kits