the one I do remember was mapping over that まだ and もう effectively functioned like 还 and 已经 in sentences, which saved me from the grief my classmates had in figuring out which to use in positive and negative contexts.
Oh, that works! I don't think I ever consciously noticed that one but you're absolutely right. (The ones that always come to mind for me are 正好 and 果然, which are impossible to translate concisely into English but work out perfectly as ちょうど and やっぱり respectively...).