this is a very interesting speculation topic.

For me, I would have liked the idea of seeing Charlie Chan meet up with famous attorney "Perry Mason" on one of the Perry Mason shows. Perry Mason first started in 1957 so the Chan who would have met up with him would have been Roland Winters (if the series carried on). Imagine Sen Yung working with Paul Drake on some detective work. It would have been interesting to see "pop" conversing with Perry on crime scene details. An interesting show it would have been.