The problem with your proposal is that the variables you chose are nearly impossible to measure. You can measure "number of bumper stickers" but how exactly do you measure "confidence" or "attraction?" These things are highly subjective and not well suited to analysis using the objective scientific method.
You could test out any number of hypotheses about female psychology, for example
No of sexual partners, versus willingness to have sex on 1st date (more partners, more willing?)
Attractiveness of male faces shown with or without females in photo (same face is more attractive if surrounded by women?)
Compare women's ranking of most attractive qualities in a man versus values (e.g. women who value family might rank fidelity top, whereas women who value fun and excitement might rank humour top?)
Basically things you can get them to actually put a number on, or actual numbers you can get out of them.
Also gives you a great excuse to go out giving girls surveys and then hit on them!
