Yeah, the Big 10 is top-heavy. They are the only conference last year where four different teams won ten games. That's great, but who did they do it against? A bunch of completely non-competitive teams.
How did Ohio State and Penn St perform in the Big 10 when they weren't playing either each other or Iowa (ie, bottom of the pack)? Penn St went 6-0 and Ohio State went 5-1. Ohio State won their games by an average of 21.8 points per game and Penn State won theirs by an average of 20.5 points per game. Real competitive, huh? (I'm not including Iowa's margin of victory against the Podunks of the conference because everyone knows Iowa deserved to go about 6-6 last year. They should have lost to Northern Iowa, but that doesn't mean Northern Iowa is anywhere near them talent wise. Ferentz is overrated and doesn't know how to motivate, but I digress.)
By comparison, look at the SEC. Florida beat Tennessee (SEC: 4-4) by 10, Arkansas (SEC: 3-5) by 3, Mississippi State (SEC: 3-5) by 10, and South Carolina (SEC: 3-5) by 10. Alabama only beat Tennessee by 2. For two Top-5 teams, don't you think they should be mowing through their conference games a little easier when teams like Ohio State and Penn State can beat their cream puffs by 3 TDs? Alabama had a bit of an easier season than Florida when it comes to how close their conference games were, but they still only beat their lower-tier opponents (excluding the two 9-4 teams they faced) by an average of 15.8 points per game.
So, do you think the upper-echelon teams in the SEC are playing more competitive games in conference because they aren't as talented as the higher quality Big 10 teams? Or, perhaps, do you think it's because the SEC is a deep conference with many talented teams while the Big 10 plays some terrible football between their worst teams?
I'm leaning towards the latter.