As a whole the ACC sucks bad, Big 10 is really not much better, I dont ever watch a Pac 12 game for more than a few minutes and get bored, the SEC is finally getting some competition other than Bama - but week in week out there are better match up games to watch in the SEC than any other conference. Its funny because 20 years ago Miami and FSU were credible programs which are basically trash today..
I think the ACC and Pac 12 suck, Big 10 and SEC are more evenly matched than it seems. SEC always has 2, maybe 3 good teams, and one standout (Alabama/LSU on top, Georgia and Auburn usually "OK"). Big 10 is the same way (OSU on top, Wisconsin, PSU, Michigan ok). Both schools will usually have one flyer as a "good" team that year (alternate Auburn/Florida, Mich. State for Big 10 through not recently). SEC usually seems to have two "contenders" annually to Big 10's one, though. The SEC has just been riding the benefit of the doubt in recent years though, e.g. Alabama being preseason #1's when they really haven't been great for a few years, they just had 1-2 tough games a year, and always against other SEC schools. Pac 12 did that for a while, until they lost benefit of the doubt. Lets be honest, the last time a Pac 12 team had a real shot at winning anything (and I'm including the Oregon team that lost the first BCS playoff), was the Matt Leinart era... which was fifteen years ago already.
Recruiting is the biggest difference though. The Ohio States and Alabamas of the world are always going to be "in the hunt" because they will outspend for big name coaches and reload better on recruiting, including paying out the wazoo for guys with NFL contacts/recruiting bases in other states. Smaller budget schools like Clemson (yes, I will put them in this category comparatively), will have good recruits while they ride high for a few years off championships/winning seasons, but as soon as they get a couple 2-3 loss seasons in there and championships seem less likely, they're back on the strugglebus with good but not great recruits. Happened to FSU, happened to Auburn, Miami, Nebraska, etc. etc.