How many different expressions and posing?

While in a dialogue, it's important to be able to see different expressions on someone's face (and some variety in posing as well). In most visual novels this is done by applying different pictures to a character and this character is simply added to a background, usually in more or less the same way every time. They typically pop up right in front of you. Because I wanted to make something more realistic, I integrate characters always in unique ways into the background. As a consequence I make different expressions and posing each time for each scene and I turn them into full pictures, even if the only difference is having a mouth open or closed. The big drawback of this method is that it takes up a LOT more memory. Each full image in my story is more than 1 MB. Currently I have around 1 GB and I think I might have around 6 GB in the end.

I don't know if there will be any serious problems with having such a file size. The engine should be able to handle it, as I read that Tyranobuilder has no size limit.

For the last dialogue I made, which was about 75 phrases (character + protagonist) I used 5 different expressions of which 2 also had different body posing. I am still thinking about adding maybe one more, but this already looks reasonably entertaining.