I'm not sure that there are any ways of 'pleasurable' dying. Maybe in one's sleep, but I wouldn't know that either. If one is trying to catch the bus, then the pain or lack thereof shouldn't really be as much of an issue as the overall reliability of the method. Thinking about the pain of it all only serves to further scare one into inactivity and uncertainty.
Right. On an evolutionary basis, we're kind of adapted to, y'know, not want to do anything that makes us die (or really undergo detrimental damage to oneself), which is why we have a bunch of psychological and sensory safeguards against most of the common ways in which it can occur. Fear of heights, pain receptors, a fight or flight / panic response, a carbon dioxide response, and so on and so forth. It's why most extant ambulatory things are still extant and not extinct. Dying being unpleasant to varying degrees is almost a given I assume, just depends on how long you have to process the fact that you are dying I suppose. But yeah, I suppose what matters more is the certainty of the death given various factors, and the lack of the ability to take it back, because you just might have that feeling in the moment, once you've seen the view form halfway down, so to speak. Don't know, I'm not an expert, nor have I ever died before haha.