It has occured to me that from a career perspective Keye Luke may have been better off not doing the post Oland Chan films.
By playing in a variety of other pictures he got wider exposure than he would have otherwise and probably honed his acting skills even more. As a result he was able to make a comfortable living as a character actor well into his 80s.
Sen Yung, by contrast, never enjoyed that kind of career success post Chan even taking his Bonanza years into account.
You actually can see Sidney Toler & Keye Luke acting
together in "The Adventures Of Smilin Jack" A very
good serial from Universal....I believe made in late
1942 or early 43....It's the only known pairing of the two actors to my knowledge...highly recommened