The new offense worries me a bit, but not that much to be honest. Peterson's track record is not great. He took a very good App State offense and pretty much kept it rolling. His last OC stop he took over an East Carolina offense that had been very good, but was trending down the year before he got there - it got worse each of his 3 years. At Louisiana Tech, he took over the top scoring offense in the country from 2012 (51.5 ppg) and had them 112th (19.2) the very next year, 2013. They did rebound to top-20 offense the next 2 years, and I did not look into personnel/injuries/etc.
But I don't think he's an innovator, each place he's been he's kept up the run/pass ratios from before he arrived. Which is kind of interesting because they differ pretty wildly - Louisiana Tech stayed really close to 50/50, he just did less tempo. They averaged almost 88 plays per game the year the scored 50 per, he dropped that down to around 70. East Carolina had been more like 60/40 pass heavy (although they dipped closer to 50/50 they year before he arrived), and while he was there they kept that right around 60/40. Then App State had been 60/40 run heavy, and he actually went even a little heavier on the running game.
None of this is in depth research, but nothing about his track record worries me like I would be facing other new coordinators. His history of continuing to do what the past offense did, Bielema's run heavy teams at both Wisconsin and Arkansas, and their solid depth at RB/OL plus the inconsistent QB and unproven WRs point to a run heavy team to the surprise of no one. And while I admit I don't have the time or knowledge to do an in-depth scheme analysis, what I have looked into doesn't make me super nervous that he'll have 20 wrinkles we can't account for. Especially with Williams not at QB.