Yote: SCAC is a district not a conference. SCAC EAST & SCAC WEST---You can't claim all 16 teams and call it a league. If you're talking about a district--I'll take District 4 over any other in the state. Kalama, Montesano, Rochester, Onalaska, Castle Rock--in the last two years District 4 has had three teams in the State Championship game. If we're talking leagues I'll take the Evergreen.
Next toughest if not THE toughest league--CTL. Followed by SCAC West, followed by Nisqually.
All that said, I think you can make a very good argument for any of the above leagues as the toughest--those are just my opinions.