Picard has better taste in ladies.
One of the common complaints about Kirk is that he is a womanizer. And while it can come off that way, he isn’t really. He ends up falling in love with every single woman he ends up with. It is more telling of him as a character than anything else but, in the end, Kirk just doesn’t have the taste in women that our boy Picard does.
Beverly Crusher ring any bells? Yes, Kirk had Carol Marcus but she doesn’t hold a candle to Beverly. She is a smart lady who raises her son all on her own (much like Carol Marcus) but she doesn’t make a big deal about it.
There is just something so refreshing about Beverly that Carol lacks and the two of them match their male love interests perfectly. Mainly because Picard is awesome and so us Beverly and Kirk always needs a little bit of work just like Carol Marcus does.
But it isn’t even just Carol and Beverly, it is every woman either of them encounter. Picard just has better taste than Kirk does and that reflects a lot on him as a character. Picard and Kirk are both lovers, it just matters which one is more your speed.