I used stuff like this, but to be honest the thing that worked best for me was to set up a Running Inside, Running Outside, and Passing Packages. Each package contained 25 plays, five from each formation that has good rushing and passing plays available (at the time it was I, WI, SI, SB, and Pro). The five plays would use different personnel (Passing QB, Rushing QB, Power HB, Elusive HB, Etc.) and would attack different areas of the field. Each play was set to have an equal chance of firing, but the auto-adjust WITHIN the package was set to high.
You would then lay out your offense like so:
1st Down:
50% Inside Rush Package
25% Outside Rush Package
25% Passing Package
(This is set up based on your preferences)
2nd Down and 7+:
50% Passing Package
30% Outside Rush Package
20% Inside Rush Package
(Again, this is based on what you feel will be best for your team and what works in Pee Wee at this time of the year and in the current sim)
Exceptional situations obviously need to be set up in the 2nd and 4th quarter, but I also liked to run something completely different at weird times to mess up the scouts from the other team.
Like in Any quarter on 2nd down and 3-6 from the 35 Yard line to the 35 Yard Line:
Mess up your scouting package.
This package would run some of the same plays as the main package, but would include different personel or would run in the exact opposite direction from the plays in the regular playbook. For passing plays I would change up the order of who was being targeted or who was targetted at all.
Again, I wasn't a very good scout, but when I played I was for sure one of the top 10 teams in the game.
Defense was run in a similar way, but I would create two-three custom D plays and then call a package to bring them in based on what formation the offence was running, where we were on the field, and auto adjusted within the package to what was working and what wasn't.
Honestly, this is one tof the best pieces of advice I can give. Back when teams were hammering the slants, the best way to stop them was trial and error. But if you only have one custom D set up, you can't compare its efficacy.