AKA League of Legends (LoL). This MOBA genre game has an interesting community. Everybody in it has an opinion and believes it to be better than high-tier players. Due to this, Designers have many problems with balancing champions. There's a problem of whether to suit gameplay to lower-tier summoners, or high-tier summoners. This leads to the designers constantly breaking champions into uselessness.
An example of this would be Evelynn, low-tier players cannot handle facing this champion in the enemy team, so they whine to Riot. Evelynn is an invisible-based champion, meaning an invisible-seeing ward can pretty much fuck her over.
That being said, I believe, personally, that the summoner spell Flash should be removed from the game entirely for a few reasons. The first being is that it promotes being reckless with no danger to yourself. I've been in several situations where only Flash could save the enemy from dying, and hey, it works.
The second reason is that the only way to counter a Flash is to pick up Flash yourself (unless you happen to be one of the few champions with insta-mobility spells). I pick up flash with 90% of my champions for the only reason that if an enemy flashes, I can flash too to ensure the kill.
For characters, such as Kassidin and Leblanc, Flash goes too well for their skillset, allowing for double jumps, and in Leblonc's case, triple jumps. Personally, I think that this is just not fair.
Ussually, with summoner spells, such as Ghost, there are multiple other summoner spells to counter it, such as Exhaust or Flash (lol). Not in the case of Flash.
Another issue with this game, is the fact that most players build items and/or skills according to the champion they pick. While this is ok (to a degree) for cookiecutter champions like Sivir or Tryndamere, for most champions you should build according to the enemy you face. Too many times I've seen an ally pick berserkers over mercurys despite the enemy team being full of crowd control. Hey man, don't do this.
The biggest problem I've seen so far, are allies that randomely go AFK near friendly towers. If you begin a game, then at least have the decency to actually play. I imagine, if told, these players would believe that /dance ing gives free experience. This is... a disgrace. I do imagine there are players like this, and this is the sort of thing that contributes to my lack of sleep, thinking of all the inhumane acts people commit.
People need to understand that LoL is a game, and not to take it too seriously. We make mistakes all the time, but it's wrong to get mad at someone for one little thing, like over a lost game. I myself suffer from this to a degree.