Sions ultimate should probably only increase speed when going towards enemies.
It's kind of funny when 75% of the time they use thier ultimate to run away before they are about to die while outnumbered. Anti-thematic, really. Instead of being a bad ass unstoppably charging into battle with a war cry, he's running with his tail between his legs at warp speed and he's so desperate to get away that he becomes unstoppable. I just imagine that war cry being replaced with him yelling out "im a pussssssy!" as he runs halfway across the map at 10% health.
: "I'm not running away. I'm running at you the long way around."