I think 8 conference games is the right number as it also allows you to schedule better out of conference games. The Big 10 should play more OOC games that are interesting to college football fans. The ACC and SEC schedule 8 to allow for the many annual ACC/SEC rivalries. I think Georgia/GT, South Carolina/Clemson, Florida/Florida St., Kentucky/Louisville are interesting games to most college football fans. Also, there are many more OOC games that should be played every year: Texas/Texas A&M, Penn St/Pitt (or WVU/Pitt), Nebraska/Oklahoma, BYU/Utah, Kansas/Missouri, Iowa/Iowa St., Colorado/Colorado St.
And, if your team is caught in a down cycle, soften the schedule to improve your record and help rebuild.