Forgive me if this has been done before recently. I did a battle thread "search" and didn't find anything similar.
Scenario 1: Battle of wits on an uninhabited planet. each combatant is equipped with a standard TNG phaser only. may use the resources of the land. zero prep time.
Scenario 2: Battle of ships - both teams' ships have the exact same armaments and defensive capabilities. 24 hours of prep.
Scenario 3: Fisticuffs, zero prep time.