Ability Draft in LoL?

The only reason I really play Dota 2 is because of this wonderful gamemode, Ability Draft.

Now I'm sure this has been discussed, but wouldn't it just be sweet to have? Some kits, like Kalista or Azir would have to be removed, and probably all manaless champions, but that still leaves over 100 champs. It would be like aram, it's a bit random, and not everything is balanced, but overall, usually fun. You could create the most slippery champ ever, that just runs around and messes with people, or the guy with the near oneshot nuke.

Was it being difficult to code the reason it wasn't added? I don't know how the coding in both games differ, but Dota 2 hasn't been out nearly as long as Lol, and it works nearly fine on Dota 2, with some glitches (Walrus punch, Tiny ult turning you into a flying pebble).

Just muh thoughts.