HotS fixes most of LoL's issues.

Get an AFK or someone DCs? A relatively intelligent AI will replace them. Intelligent enough that if you ping it somewhere it will follow up.

Have a bunch of elitist "I carried this game, you all suck" mouth-breathers on your team? No problem, there essentially isn't a KDA system and all kills/assists are given to everyone who participate in the takedown.

Someone feeding or someone getting a lot of kills? Again, not a problem, the shared XP makes it so no one single person can get so fed they can 1v5 the entire enemy team and make it utterly impossible for your team to make a comeback. ^ And because of that there's a lot less toxicity. If someone "feeds" you don't have a whole team raging at them because they single-handedly give the enemy the team the game for making mistakes.

Never thought I could have this much fun on a Moba again.

Over-all, the game focuses more on the team, not the individual. LoL currently panders to people with egos by having champions, and a system, that allows them to get so far ahead or behind that a single person (like an AFK or troll on one of the teams) can decide the fate of the entire match.

Both are fun games, but provide different experiences.

If you want to feel important and stroke your own ego with your "x-champion mechanics" and carry an entire match by yourself, then you play LoL.

If you want a genuinely fun team-oriented gameplay experience where even the weakest members can contribute, then you play HotS.