Here's a change that was asked for a long time in ARAM...
Remove creep block, or at least allied creep block.
A lot of people actually argue to remove it even in SR. I don't see why it shouldn't be removed in ARAM in a map slim enough that minions (who are more numerous now because of recent changes) are cramped against each other to create a giant wall to countain 5 champions who are already cramped against each other.
To be honest, it would be the best change along with bans that ARAM would've ever get.
if you happen to have him.