I can't imagine why you would think that the typical casual fan wouldn't know who Chamique Holdsclaw is: she's received major national coverage. In fact, aside from Sheryl Swoopes (sadly, for reasons having nothing to do with basketball) and Diana Taurasi, I'd hazard a guess that Holdsclaw might be the most recognizeable WNBA player to casual fans and non-fans in the league today. I mean, when she came into the league, people were talking about whether or not she was good enough to play against the men!
So, Swoopes, Leslie and Holdsclaw are no-brainers to me, in terms of notoriety. My argument is based on the fact that the WNBA Finals at least make it to ESPN, so the casual fan who might have tuned in for the playoffs would have at least heard of Thompson, whereas Smith's best years were in virtual anonymity in Minnesota.