I think the WNBA has very similar problems to Women's football (or soccer) here in the UK. The sport has a long history in the mens games and comes with generations of followers. The women's game can at least benefit from some of this prestige but at the ends of the day it doesn't have a lot of heroes and history itself. There is no quick fix for this. Just a lot of hard promotional work and some lost money early on in the development of the fan base is all there is to do.