I built the old Matchbox kit and converted it to RC almnost 30 years ago. I used a scale size prop and the scale rudder, and had no issues with running it that way. IMHO, you don't need an overscale rudder-- if you're concerned about the turning diameter, you can go with greater than scale deflection.
I think the Flower is the perfect plastic model for RC conversion. It is big and beamy, with a displacement of about 5.5 pounds, and looks great on the water, even "rough" seas!
I saw the contents of the new Revell Platinum edition just last week-- ti was nicer than I was expecting. The wood decks are not those over-thick plywood things--it is a sheet of real wood veneer with adhesive backign that is abotu the the thickness of a vinyl sticker. I found it interesting that Revell repeats the Matchbox error by providing the wood veneer for nearly the entire model, when the real FLowers only had a small amount of wood decking. (The guy who was building it was only using it on the foc'sle bridge, and are by the K guns.)
I was also impressed by the nice metal barrels that the Platinum kit includes. plus the nice PE set.
Bottom line: If I was to buy a model today, I still don't think the Platinum kit is worth it, unless I was doing a diplac model. For an RC project, the old kit would be good enough.