In terms of sex scenes, the alpha path goes a bit further than the beta one. The mc gets to have vaginal sex with both female leads, as well as with minor or supporting female characters; whereas in the beta path, the sex scenes between the antagonist and one of the female leads, not counting the dream sequence, so far end with blowjobs.
But I would say the sex scenes are hotter in the beta path, in no small part because they play on the jealousy of the mc (and those players who may identify with him) . And if the masochistic fun in the beta path lies in competing for female favors and losing, you don't get the satisfaction of reversing this situation in the alpha path; there's no thrill of winning the competition, you just have sex.
Come to think of it, the antagonist in the beta path, being the alpha male, should probably be called the protagonist instead