Well, you don't seem to have any shrink on your cells at all. That's a big no-no and opens you up to a real risk of shorting them out. So get some single cell shrink on them
But, cells have always sat in chassis like that and I have never known it to be a problem. If you are concerned put a little duck tape or similar across the cell slots. Maybe even get a sheet of the chassis protector that Associated sell.