This kind of reminds me of one of the features of the C&C:G:ZH mod Boss Generals called General Plans.
You start off with a relatively basic (Though still competitive) force, but can choose a plan on what kind of strategy to focus on. An Assault plan unlocks powerful frontline units and abilities, Shock and Awe gives you awesome hit and run forces, Demolition gives loads of nuke AoE, Toxin DoT, etc. etc.
This contrasted with the later unlocked 'abilities'. Whereas the abilities served as a quick game changer with things like a few free units or a one-time bomb, the plans focused on overall strategy with simple unlocks.
You initially could only choose one, but you come back and unlock the others later to allow you to shift strategies and expand your forces. They proved quite popular and very fun.