Reducing Snowballing is probably the best way to Improve Pro and Normal play in one Fell Swoop.

The problem in pro play is that the games can sometimes get really stagnant and slow because the players fear that one false move could trigger a snowball that would inevitably lose them the game.

The problem for Solo Que players is that 75% of their games feel like stomps in either direction, leaving only 25% of the games as even and enjoyable slug fests.

I'm not saying they should make leads not matter or anything, but Riot should really consider tweaking snowballing a little, because it would probably help the game as a whole quite a bit.