Much like your friends, this discussion can go on forever without agreement.
The one issue I have with the general maxim that the SEC is the toughest conference is this:
People often say "the SEC is the toughest conference to play in," I would say that is only partially true. Much like the other conferences that have more than 10 teams, teams in the SEC do not play every other team in the SEC. Each team plays every team in its division, and two teams in the other division.
Since the SEC west is far weaker than the SEC east right now, those teams in the east have a tougher SEC schedule (not considering non-conference teams).
Take for example Auburn's schedule:
Sat, Sep 1 Kansas State
Sat, Sep 8 South Florida
Sat, Sep 15 Mississippi State
Sat, Sep 22 New Mexico State
Sat, Sep 29 at (4) Florida
Sat, Oct 6 Vanderbilt W 35-7
Sat, Oct 13 at Arkansas
Sat, Oct 20 at (5) LSU
Sat, Oct 27 Mississippi
Sat, Nov 3 Tennessee Tech
Sat, Nov 10 at (21) Georgia
Sat, Nov 24 Alabama 1:30 pm --
The only top teams on their schedule are South Florida, Florida, LSU and Georgia. Alabama is always a big rivalry game, but we'll see how tough of an oppenent they turn out to be by the end of the year, so we'll call them a mid-tier opponent for now, along with Arkansas. After that, it's all bottom feeders in Vanderbilt, Mississippi, Tenn Tech, N.Mex State, K State, Miss State. Every team schedules a few "push-over" games, but most teams don't schedule 6.
Now, compare that with Florida's schedule this year and you have two different scenarios. Almost every team in the east has a really tough schedule (with the exceptions of the non-conf games).
But then you factor in the non-conference games. SEC teams typically play 7-8 conference games and 4-5 non-conference games. For the whole SEC conf this year, 10 teams play Div-1AA opponents, 12 games are against Sun-Belt conf teams (the worst conf in the nation); thats 22 games against D-1AA or Sun Belt schools. 72% of the non-conf oppenents are non-BCS schools.
So, a better statement would be to say, "If you play in the SEC, you are likely to play some of the toughest teams in the nation." (rather than playing in the SEC is the toughest, because any given year, one team might have a cake-walk.)
My suggesstion for every conf, including the SEC is to reduce the number of teams down to 10, so that every conference team plays every other conference team eliminating the need of a championship game. The more teams that play the same teams, the easier it is to compare schedules, wins, and quality. I think this would make it easier to rank the teams for purposes of the National Championship.
Ok, I'm done.