To me scale is 90% about building. They are really just big models that also fly. Once a model is in the sky you can't tell the difference between a scratch-build precision scale model and a sport-scale ARF. I can see buying an ARF as a sort of trainer for a particular scale subject (like buying a Hanger 9 Corsair while you build your own true-scale version) but since scale really is all about building AND DETAILING you might as well get started right away on a project that will help you develop those skills.

And since we are talking about developing a skill set you should think about that kind of planes you really like and the sort of detailing that will be needed. For example, if you (like most people into scale it seems) are into warbirds then you better start learning how to do rivets, panel lines, and scale retracts. On the other hand these are unneeded skills you prefer WWI era planes.

If I were interested in WWII (which I'm not really) I'd be looking at the excellent kits from Skyshark. Personally, I don't think I could stand to add one more Cub to the current pile.