Also, while Cullen was a seasoned host by this time, I really don't think he's a "big name". Just my opinion.
Within the industry, by this point, absolutely he was a big name.
Really? Seriously? Oh, c'mon...you're pulling my leg, right?
You don't think Bill Cullen was considered a "big name" in the world of game shows in 1974? Not only would I believe him to be considered a "big name" by many/most, very few other hosts were at his level and I can think of only a very small number of hosts who might have been considered "bigger" than Bill Cullen in 1974.
And, for what its worth, just for the sake of arguement, let's say he wasn't considered a "big name" by the industry or even the viewing public at that time. However, to one man in particular, I think it is safe to say that Bill Cullen wasn't just a "big name" in his mind but was, whenever possible, the ONE name that always topped his list of go-to game show hosts. That man, of course, was Bob Stewart. I'm only guessing here but I suspect that if Cullen wasn't already committed to another network daytime game show in March 1973 (NBC's THREE ON A MATCH), he would have been Stewart's choice to host the CBS daytime version of "THE $10,000 PYRAMID" rather than Dick Clark.
Don't get me wrong...Dick Clark RULED throughout all his years of hosting the various PYRAMID incarnations and I can't imagine the show without him. I just think he was a very fortunate man due to Uncle Bill Cullen being unavailable at just the right time.
JakeT