More sophisticated case of "me and I"!

"Me". You can judge this by considering the following different ways to say what you mean: "it will be just us" and "it will be just we". Now if "we" sounds wrong to you, then "I and you" should also sound wrong and for the same reason: the pronouns "we" and "I" are in subject case. So if you prefer "us", then also prefer "me and you".