I'll give the Lindsey stuff a closer examination some time.
As far as Angelus goes, I don't see Angel and Angelus as entirely separate people. Angel remembers the things that he did as Angelus. His soul carries that guilt. That's part of the curse: Angel has the soul of a man, but he's not a man. He's still a vampire. He's still Angelus. He's still evil. But he's *also* good. The torture of the curse is that he still craves blood, but that he hates himself for craving it. His soul makes him feel guilty not just for the things he did in the past, but also for the drives and urges that never leave him. Imagine how miserable you would feel if every time you passed a child on the street, you saw yourself reaching out, plucking that child up to your chest, sinking your teeth into its flesh, drinking the life out of it, dropping its limp body to the ground, and then stepping on or over the wasted carcass -- and enjoying the look on the helpless parent's face, to boot. It would be like living in two realities. In one, Angel has the soul of the average human, a soul that considers some things unthinkable and unpardonable and horrible. On the other, he has the body and the brain and the memories of a vampire, a creature who is burdened by not such restraint. His vampiric side is constantly in conflict with his soul. That conflict is what makes Angel such a fascinating character. Angel is so straight laced and repressed (in every possible way) because he is constantly struggling to stamp down his evil, vampiric urges and to do the opposite of what he wants to do. That's why he saves people rather than eating them. It is precisely because Angelus and Angel are NOT two totally separate beings that Angel suffers. At least, that's my opinion of the way that the soul works for Angel.
So, while I agree that Angel would never in a million years do even a tenth of the things that Angelus would do, I disagree that they are so separate that those drives aren't even there. I think Angel wouldn't do even a tenth of the things that Angelus would do because those drives *are* there and because he desperately wants them not to be. The cruelest twist to the curse, of course, is that if he feels that one moment of peace that he would feel if those drives did ever cease, they would be back in full force and with no soul to stop them. So not only is angel is constant conflict over what he has done and what he wants to do, he's also in constant conflict over what he MIGHT do in the future. Honestly, I'm amazed that he's not sitting in a corner and wetting himself. That he has any shred of sanity at all, let alone that he fights evil and does so much good, is a testament to the strength of his character.
Basically, with this as my view of Angel, I think Angel still wants to have sex with men (or man-pires) ever bit as much as Angelus does (which, granted, is way less than he wants to kill, maim, torture, and drink the blood of the innocent). I just think he avoids the behavior because it's part of his vampiric nature. Thanks largely to his coping strategy of disassociation (compartmentalizing "Angelus" and "Angel"), he has become pretty good at keeping a lid on anything he considers vampiric. It's when both the vampiric side and the souled side want something (like, say, Buffy) that Angel *really* gets into trouble.