I'd prefer Budd lightweight consists such as NYC Empire State Express, California Zephyr, Wabash Blue Bird but would go for smoothside sets such as PRR's Broadway Limited too. Will also second the motion for a consist of PRR/LIRR P-70 coaches - please add a B60 baggage car though if you will do P-70's!
Will try to support these but it will depend on how many different sets come out and how close together they will be released so I can pay for them. If this becomes reality can I safely assume the first sets won't be out until winter 2019 or later? If that is the case I can plan for reserving a few sets.
I assume if (yes, I know it's a BIG *IF*) these proposed sets get strong reservations there is a chance consideration will be made for producing the matching locomotives in S which would be E7, E8 and/or PA's? I imagine since you've already done these in O it cuts down on the research/design time at least.