So, my thinking has been that the LD trains should be standardized into one or two "types" (something in the 9-11 car range and something in the 13-16 car range for the respective types ). This would allow the LD order to "simply" be a bunch of trainsets.
Now, this leads to a complication with the two "split" trains (the LSL and the EB). My thinking is that both should simply be made into two trains (one going to each endpoint) so as not to have to deal with splitting trains. I'd add the proposed North Coast Hiawatha, Sunset East service, and a daily Cardinal/Sunset to the plan - all four have had consistent political pressure to do happen, and in most cases the studies seem to say that the numbers work. IIRC this would come to something like 66-70 sets plus spares (so probably about 80-85 sets, ignoring the Auto Train both as sui generis for now and as something that could be run with displaced Superliners for another decade or two if need be).
 My thinking is roughly as follows:
Short: 1 bag, 3-4 coaches, 2 food service cars, 3 sleepers
Long: 1 bag, 4-6 coaches, 2 food service cars, 1 sleeper-lounge*, 4-5 sleepers, 1 dorm
*I'm thinking that this would have 1-2 premium bedrooms and the rest of the space would be a lounge which could partly be used for dining overflow. Allowing for coach pax "buying in", a single single-level diner starts to "max out" around three sleepers, but having a half-dozen tables a la the PPC would move this threshold up by about two sleepers (two full seatings in there would correspond to 48 pax).