Are 20 Sounder cars still mothballed from the pandemic ?
I'd say add one such car to each Horizon set, put the "shorts" in it, but with the maintenance meltdown in Seattle, not practical. If Northstar and Dalles TRE operations quit, there are those cars and locos.
Commuter seats would not be popular, but what for those narrow, hard seats in upcoming Venture cars on Airo's. No one will be happy then.
I don't know if the Airo trainsets coming in 2026 are anything to look forward to given the horrible Charger loco situation in Chicago, not very impressive ALC-42's on LD, and VIA Rail's version.