I started playing League of Legends first before all of the other fancy MOBA games out there. Afterwards I tried DOTA 2 for a bit but it did not really appeal to me as much as LoL does. Heroes of the Storm is neat, but it doesn't have the diversity and customization of items and whatnot that I enjoy in DOTA 2 and LoL. There is toxicity in LoL, which seems to be the thing everyone jumps to when talking about this game, but that's in pretty much any other online game community you'll find. That's why there's a mute/report function. I've been playing since season 1 of LoL, and have encountered my fair share of trolls/not pleasant people, but for the most part it isn't as bad as some may think.
so there's my $0.02