I'm starting the 1/48 scale line with the same product I started the 1/72 line with...Concrete Hardstands. The first two are rectangles, a 9" x 12" and a 12" x 15".
The 9x12 is suitable for single engine props and small jets such as A-4's, F-5's and T-33's. Larger planes will fit with overhang, especially if turned diagonally.
The 12x15 will fit a F-4 Phantom comfortably, and a F-15E set diagonally.
As you can see, I haven't included the pre-molded ground work areas. I realized they are easy enough to do yourself if you want them, and if you don't want them, now you don't have to have them!
You can check the ground work hints in a few days to see how I do it.