Depends how you define "solid reason". If you're alluding to reproductive quality, I agree, it doesn't add up as much as height does.
There is however the social stigma of being bald -- especially for white and asian guys in the US -- not sure about Europe.
I, personally, would pick a mate who's not socially stigmitized over one who is. Maybe women feel the same way about bald guys? Don't want their friends to make fun for dating a bald guy? (of course, some dudes look worse being bald than others)
Maybe itīs a stigma like you say. But I also agree, when it comes to reproductive quality it shouldnt matter. All I can say is thank god for new technologies, Iīll probably be bald by the age of 35 (im 23 right now), but now there are various solutions to male pattern baldness.