The handicaps annoys me, to be honest. Despite the vanilla nature of it, it definitely feels like I’m not playing the game the Devs intended me to play. Honestly, I’d rather the difficulty gave bonuses to the AI over penalties to me.
I usually play via slider manipulation or ExpertAI, but wanted to try without because I hadn’t previously played as the USSR beyond '38 in vanilla and so didn’t have any of its achievements. You can definitely see the effects of not playing ExpertAI in my current game. Particularly in how there’s no way I would manage to hold a mostly static front with Germany in '41 with it enabled.