C-5 would be too similar to the D11. Basically a D11 without WEP and no aux tank (?). The aux tank is tiny and the WEP is the least effective of all Jugs, especially without the paddle blade prop to make the most of it, so D11 is a fine stand-in for scenarios and events.
The most significant model we are missing in the Jug line is the D-23: a Razorback with a paddle blade prop and wing mounts. This is more representative of a typical 1944 razorback than even our D11 since almost all earlier D's were retrofitted with the paddle blade prop and wing mounts. Retrofitted Razorbacks continued in service along side the later bubbletop D models.