I have updated my schematic and the bill of material. I've added a bunch of small components to take care of a few issues. I also added a field for cost per cell which comes out to a pretty decent $7.34/cell (before shipping), if you go up to a 48 cell system you're down to under $3.70/cell.
The code is not updated. It has quite a few changes and I am fairly sure nobody has browsed through it in depth yet because I haven't had comments about how this and that won't work.
I've fixed most of it with individual testing of one part here and there. I'm sure there will be bugs to fix once I try to get everything working properly together. I'll repost the code at that point.