For me there would be a lot of fun.
I don’t agree the workload in B737 is smaller. Programming FMC alone takes more time than starting up 35A. And during a flight there is not much to do in the latter. Monitoring speed, due to lack of auto throttle, is the only thing you need to pay attention to. It would be more challenging if it didn’t have GPS installed.
Flying Piper PA-24 from A2A is more engaging than 35A because literally every system can break in this plane.
For some reason you excluded BAe 146 and F28 I mentioned, both are from the same era and are way more complicated to fly and operate than 35A. Still flying them as a single virtual pilot is not a problem.