1) Well, I have very long legs and particularly femurs, but it's never been an issue, and I don't think it should be an issue with any physique. The first pull really is just needed in order to get yourself set up for the second pull, which you can't really do effectively any other way.
2) You may need to push your knees out during the first pull. This may lead to some discomfort with your arms halfway through the first pull, but I'd still keep them outside the knees. It's essential for setting up the second pull, and this might let you be in a better position to do so.
3) It can be a mobility issue. Alternatively, pushing the knees out during the first pull may help.
4) I remember seeing an interview with a Chinese Olympic gold medalist who said that even after 20 years of training, neither lift feels comfortable for him. So yes, I would definitely learn the correct technique and disregard comfort.
5) I've never heard of this. My stance has always been the same for both lifts, just with different hand placement. For the sake of consistency, I think that's probably the best way to go. When you get to the squat position, there may be some slight variation between the two lifts, but I don't see why you'd want to have a different starting position. Once again: not saying it can't be done, just I've never come across it and don't see why you'd want to do that.