Name few viable diverse strategies, without mentioning 0CP call-in units and "strategies" where difference is 1 unit. You can skip soviets tho, because they at least have some sort of different options with cons\penals\clowncar and so on. What about others?
Random goofs vs 4 digit rank wont cut it, for oblivious reasons.
Well just as an example, if I'm playing OKW I can go 2 Sturmpioneers and either a Volksgrenadier or a Kubelwagen instead of just spamming Volksgrenadiers, if I use Elite Armour I can supplement this with a 221 which is particularly useful against Maxim spam. From there I can feasibly focus on a strong mid-game by building the medic and repair trucks, relying on closing the game out with light vehicles (Puma + HVAP is a reliable medium tank killer) and support weapons (MG34, Raketen), or I can rush the flak truck and start pumping out Obersoldaten and saving for either a Panzer IV or Panther depending on the situation, which I then also have the luxury of supplementing with a Sturmtiger if I need a heavy breakthrough unit.
Or, if I play Brits, I could spam Infantry Sections and go for Bolster early (boring), or I could build Sappers and a Universal Carrier, supplement that with a Vickers or Sniper (more applicable to OKW), use the Assault Officer to fill any infantry gaps, mainline Commandos, and use the fuel savings to get an early AEC or Comet, again, depending on the situation.
So there's several branching paths I can take the game down in both cases.