Indeed. IMO it's a shame that the best results aren't achieved with a well-balanced Shepard (which isn't necessarily a 50-50 one).
Very few people have ever claimed that any of them are totally good. Your post read though as a criticism of anyone who expressed an opinion on them at all - there's nothing wrong with thinking that some options are better or worse than others, and that of those some are going too far.
For what reason, though? Take Synthesis, for example. You can argue that people's biochemistriy shouldn't be changed without their consent, and that following this principle is worth accepting the downsides of one of the other ending options. I would argue, however, that this is all about you and not enough about the galaxy, an ultimately self-centered way to think. The argument "You don't have the right to make that decision" is hypocritical. You've been making wide-ranging decisions all the time, and that you like this one less than the others is no reason to discount its legitimacy. The thing is, like it or not, you are in a position of power like nobody else ever was in this story, and like anyone else with the power to make decisions that affect many others, you will inevitably tread on someone's "rights". The only way in such a situation to keep your hands clean is to do nothing, and then everyone will die. You aren't playing God, you are given a god's power and asked to act responsibly with it, asked to accept the admittedly crushing responsibility that comes with it. The argument that you shouldn't "play God" is denying the situation. With a word or three, you are going to set yourself up as a god, make galaxy-wide changes to life or consign one species and the remnants of countless others to oblivion.
IMO the decision shouldn't be about you and your principles. It should be about what's best for the galaxy. We've been arguing about that forever, but I find people are stubbornly unwilling to accept that anything they feel uncomfortable to bring about because of their principles can actually be good. Thus, people claim the endings are all bad. However, there is no necessary connection between your principles and the outcome of any decision that breaks them.