@Meddler: What are your thoughts on a highly-mobile Support Champion?

ITT: Haste effects don't count as "highly mobile".

When looking at the support Champion roster, none of them really qualify as having high mobility (think Lee Sin, Nidalee or Ahri). Braum, Leona and Alistar might have the ability to dash to appropriate targets, but they don't have multi-dash capabilities or something of the sort. Thresh doesn't count either, as he can only pull himself once per Death Sentence, and Nautilus... well, you get the idea.

To break the mold a little bit, I think it'd be awesome if at some point, Riot were to create a support Champion who has extremely high maneuverability, and thus is able to keep pace with highly mobile teammates like Nidalee, Kassadin, etc. Whereas other supports would be left in the dust behind those multi-dash/multi-blink Champions, this high-mobility Support would be able to follow them pretty closely.

"Isn't that just an assassin?"

Only if the Champion is geared toward killing, which Supports are not. You could easily have low damage (and scaling) on such a kit and compensate with crowd controls, slows, shields, etc.

"Highly mobile Support? Unfun to play against!"

Possible downsides could include low range, poor ability or even inability to poke, and requirement to take a lot of risks to get rewards. Remember, there's a lot of ways to give new Champions a disadvantage that can be played against.

Wanna chime in? (Speaking of which, Bard doesn't count either, as Magical Journey is an awkward case that I don't count as combat mobility.)