I agree spread teams tend to have weaker/softer defenses as I said above. That is a drawback but I take a look at everything in totality and on balance I think it's still the best avenue to outperform your perceived status on the landscape.
Really, I couldn't care less what we do, all I care about are lots of Ws and being ranked in the top 25 as often as possible. It's just after observing enough football and seeing what's been going on around the college landscape, I think a spread is the best play to improving ourselves.
I've also said I think it's much more plug and play friendly. How many times have we heard we're too young in this position group or that position group or this person is hurt or that person is hurt. To some degree those can be legitimate excuses but it's college football. Players are always graduating, faces are changing, people get hurt. You have to adapt to the environment you're operating in and a spread seems to lend itself better to that. We've seen in with Brian Kelly at Cincy using multiple qbs, Baylor has had various qbs and keeps humming, OSU last year, Oregon to some degree although struggling a bit this year but still doing okay on offense at least. So while it may not be a cure all to the changing faces on your team, I think it's better suited to handle it.
I think TCU 6 players to injury and off the field issues on defense but they're still able to perform, Memphis lost 8 starters and 5 backups and their defensive coordinator and they're still doing okay so far. To some degree the offense is able to make up for the defensive deficiencies. Eventually it may catch up to them but at least it's something to counterbalance the losses. I think a defense in the 50-70 range on scoring/total should be good enough, it can't be something that is in the 90s/100s. So I think if you can eventually create a mediocre, not great, defense and couple with a strong offense you'll land up somewhere good.