I know it'll still depend on team talent but is there a particular playbook/offensive style that seems to work best in RO leagues ?

never done any research to back it up.....but run focused seems the best to me. the more my teams run the better they are.....love it when i see my qb is 4/7 for 70 some yards

if you check out my teams histories and head coaches you will see that they are all run focused and my teams are always near the top in rushing categories. i make the playoffs often

the pass game is "broken" with current engine. recievers rarely get more than 700 yards in a season while multiple running backs have twice as much

I agree to frank. But would be interesting to know how much impact each Coaches offensive style has. Is it only the HC or also OC ans position coaches? I sometimes got the feeling a run focused HC is not enough and my teams still passed to much in the past.

HC controls the playbooks and the game plans. OC and DC are only there for player development.

Totally random post, but roster only leagues need to have overrides.
Just my two pennies - which they don't make anymore.