Summoner Spells deserve an update
For how integral the summoner system is there's far too little variance and satisfaction from most of them.
is mandatory. It's probably a decade too late to fix this.
are the only two that can make interesting plays happen.
are basically just stat sticks and don't really provide much gameplay, but they're very annoying when appropriately strong
was so bad it got removed from the Rift, pretty sure it's ARAM-exclusive now?
are hardly used at all
The best way to dethrone Flash would be to either make new summoners or rework others into things that give you similar playmaking power, either by proactively enabling your own plays or by reactively denying another play, in a way that isn't purely numbers-checking the other player like Heal, Ghost, and Barrier tend to do.
Summoner Spells have so much potential to boost fun factor a lot and it's a shame they've been relatively glossed over in a game evolving as constantly as LOL.