I don't think that future engines, like A8 in 2 years, will still support C-Script. When you use C-script you're probably restricted to A7, and even with A7 many of the new features only work with lite-C. So a game in C-script can never be as good as the game in lite-C.

Additionally, in my opinion programming a game in lite-C is around 30% faster than in C-Script. This is because lite-C does not have all the C-Script restrictions and limitations that you need to keep in mind. All the lite-C samples, would be a lot more complicated when they were programmed in C-Script, if that were possible at all.

I think, it is certainly worth to convert your templates to lite-C.