As I understand the head coach performs two functions 1) has some influence over player development and 2) determines the offensive and defensive playbooks. As a beginner this season I focused mostly on hiring a head coach with the highest score possible but now I am starting to realize the differences in playbooks is at least as if not more important. Can anyone give some advice as to the offensive and defensive coaching styles that are preferred...or conversely the styles that should be avoided? Thanks!

I can tell you the Run Focused 3-4 style does not contain 4-3 Normal plays.

If you want to use the 4-3 Normal Man OLB Flat Zone play as your default 212 defense, pick a different style. As setherick recently pointed out, there are other options for defending the Hitch and Slants, but most owners default to Man OLB Flat.

Pretty much any offensive or defensive strategy can work but everyone has a different "best" version. The first thing to realize is you want to select a style suited to your team. For example if you have 2 good dt and 1 good MLB you'll want to go 4-3. You'd want to go 3-4 for the opposite. Next you'll need to look through your DBs. You'll need to determine their zone or man cover ability. You'll select your type of 3-4/4-3 from that. On offense it's much the same, you just play to your strength. It gets more complicated later though as your team and coaches gain familiarity with the called and scouted plays. If you change styles you could end up with lots of unfamiliar plays, lowering your effectiveness. So you have to weigh the value of changing your system with the potential loss of familiarity. Ideally you want to select younger coaches who will play a long time together or at least keep the head coach to the same system. While high stats is great, what is most important for coaches now is their system and play familiarity. If you have a coach who has been in your system for a few seasons he actually carries more weight than a slightly better coach as far as outcomes.