Maybe try looking for a raw banana pie recipie for some inspiration? I've seen a lot of those that use sliced bananas and nuts. Maybe modify it to do what you want? bananas, nuts, and chocolate are a good combination!
I've only made a banana pie with tofu. I don't think using faux cream cheese would be bad, might even taste good. Make sure the bananas you use are really ripe and sweet or the pie will be a little bitter.
now i want to make a pie!