1. No more than 11 players are allowed on the field after the Defensive Coach says "set." (Offense choice of 5yds or result of play)
2. All defenders must maintain at least a one yard neutral zone - base and body - from the LOS. (Offense choice of 5yds or result of play)

Whatever style is played, these 2 would cover them all, I think. Stack, 2-man DL, 10-1, whatever YOU wanna do on D is YOUR prerogative.

And no magnets allowed on metal fields to hold your guys in place unless it's a Penalty when the other team runs into you.