Chip Kelly
Les Miles
Bill Belichick
So your top 3 are:
1. A guy whose offensive play calling ability seems to have completely disappeared since his second year in the NFL and has zero regard for recruiting or developing defensive players, something Oregon lacks.
2. A guy whose offensive philosophy is to run his running back into the back of his offensive line 30 yards a game, was a barely over .500 coach at Oklahoma State, and didn't finish in the top 10 his last 4 years at LSU, and didn't win double digit games his last 2 full years.
3. A guy who is 64 and has never coached or recruited at the college level in any capacity and currently gets to coach in the second worst division in the NFL pretty much guaranteeing him a first round bye every season and also has the most secretive contract of any head coach in the NFL.
Miles *might* be the best option of those 3 simply because he's been a college coach more recently and if you could somehow pair him with a decent coordinator (heck even keeping your current offensive coaching staff might work).
The thing is though, when someone drops 70 on you, that isn't about who your head coach is, its about a disparity in talent level. Oregon's current recruiting class has only 3 defensive players in it (and 5 athletes so some of those guys might be on defense).
Looking at the last 3 years they've recruited:
8 LBers
5 DT
9 DE
10 DB
So 32 guys whose primary position was on defense in HS, plus whatever ATHs they converted. Right now they have only 4 Juniors and 1 Senior on defense. Most of the backups appear to be Freshmen and Sophomores as well.
I think it is easy to panic, and maybe there's evidence behind the scenes that the Brady Hoke experiment isn't working, but it almost feels like this is an aberration that if the Ducks panic they could make worse. Shrug.
During the Kelly era the Ducks were ranked 22nd, 5th, 9th and 4th in FEI defensively. They were 16th, 3rd, 12th, and second in S&P+ during the same time span. This year they are 116/115 in both. Since Kelly left actually they've gone 25, 28, 85, 115 in S&P+. So I guess the question is what happened between 2014 and 2015?
As best as I can tell the big things are a lot of departures either due to graduation or the NFL on defense and also the fact that they switched from running a 3-4 to a 4-3 as well as the retirement of Aliotti back in 2013 all kind of caught up to the Ducks this year, couple that with the injuries and that would explain their sharp decline.