You really really need to read the books. As they progress you will find many of your assumptions are incorrect.
Robin has her own scars and baggage that was barely hinted at in series 1 on TV. Strike is very much not a commitment phobe, he is a survivor of domestic abuse.
Robin is supposed to be attractive in a girl next door way which is highlighted in her reactions to Lula, Ciara and Charlotte who are supposed to be model beautiful. Later plots also rely upon her being an attractive woman.
Strike is supposed to be sexy but not be handsome, that is supposed to contrast with the more clean cut "good catch" Matthew.
I don't really have a problem with it. JK has issues she wants to explore in these books and she has written characters that allow her to do so.
If you want female leads in crime fiction may I suggest Val McDermid, Kathy Reichs, Karin Slaughter or Patricia Cornwall.
Kathy Reichs even has an alcoholic female lead with a pretty boy on/off boyfriend who she is reluctant to commit to.
Interestingly Val McDermid has written some fab female leads (Lindsey Gordon, Karen Pirie, Kate Brannigan) but the only ones picked up for TV is the Tony Hill and Carol Jordan series. Jordan is a senior detective, hill a consultant, they get fairly equal billing in the books but on TV they are all about Tony Hill.