Well, I mean for almost every champ 
is a must take, and it hurts variety in terms of Summoner Spells.... why don't we make it a third summoner spell... we could make the same with ghost, so you can choose between a movement boost and a blink, and take 2 of the other summoner spells.
I´m saying what if, I am not saying: implement it, this is me just wondering how the game would be with this.
xSleepy1 votesi dont mind the idea of 3 summs so much, but every champ in the game (with the exception of shaco and maybe top lane hec if you're running 
)is gonna run either 
or even both. it's the same choice you make now basically.
in short, i feel like adding a 3rd summ is just adding a 3rd summ, not really making mobi summs free.
Cherysse4 votesMaybe they could add classifications for summoner spells, and you can choose 3 summ spells but only one of each tipe (I included smite in each category so that jungler's don't loose the spell they want.
**Offensive: ** 
(if reworked instead of being removed) 
-add more spells rito-
Defensive: 
{{summoner:2}} (if it ever returns)..
Mobility: ....
Deep Terror Nami1 votesMake a new thread for that.
bluekhezzy1 votesI like this idea even if its just for two summoner spells.
TendajiX1 votesTeleport should be mobility.
Cherysse1 votesWell I've placed it on offensive because many toplaners need flash to reach their targets (else they would just become kited to death), and In order to use TP you sacrifice your offensive summ.
Cherysse1 votesHey Guys, Ive added a list of possible summ spell combos that could be achieved with this 3 summs + classification limitation:
Combinations List:
- -( or ) ADC pick
- -( or ) Supp Pick
- -( or ) TOP Pick
- -( or ) TOP Pick
-{{summoner:2}} / -( or ) Siege/Poke Pick
- -( or ) Assasin Pick
- -( or ) Offensive Jungler Pick
- -( or ) Chaser Jungler Pick
- -( or ) ALL-GANK Jungler Pick
- - ALL-IN Jungler
- - ALL-IN Anti-CC Jungler
- - DEF-EM ALL Jungler
- - / Sturdy Jungler
- {{summoner:2}} - / Tracker/Counter-Jungler
- {{summoner:2}} - / Too Much Pressence PICK
- - Hybrid Sustain Pick
Now you would actually get a lot more choices
Cherysse1 votesThey can't run both / with this change, unless flash were to become the only mobility spell.
Deep Terror Nami1 votesSomething would just take its place as a near 100% pick. Probably TP or Exhaust if the person doesn't already have it. 3 years later "Make TP a baseline ability".