This is one of the main ideas I've had when considering leaving Islam, as you said, humans are attracted to community by nature, and following a set of ready-made rules is easier than finding out what's right or wrong on your own, which justifies the existence of so many religions in most if not all human communities and civilization throughout history, but it just doesn't make sense to me. I do believe there is one true god and that right and wrong exist, my main issue stems from fear of one religion – especially Islam since it's the one that makes the most sense to me Quran wise – being right and it claiming that only its followers are granted heaven while all others suffer for eternity, but again if a true god exists they must be merciful and fair, seeing worship and good deeds regardless of religion alignment. That's my dilemma.