A standard deck box for the big cards will work for the mini cards, especially with sleeves. Just turn the mini cards sideways and they fit! Problem solved! At least until "they" figure out a mini deck box that works better.

Edit:

If you only have a small amount of the mini cards, then you can fit them in sideways and standing up. I have way too many, so I lay them facedown and stack them. Getting them out isn't exactly fun, but I was thinking about glueing the lid shut and cutting the box in half to make it more like what we would need.

Side loader deck boxes work the best, they are almost the same height as the cards, sleeves work even better in these with a little space for the rule cards.

i really need to find something for my cards.. I've been using the plano plastic divider boxes (where im also holding my minis). It works fine for the mini cards, just hard to get em out without mixing them all up.. need to upgrade my storage.

I keep mine in small compartments of a Plano tray, using cardstock dividers with labels on them. You could cut index cards to the right size.

I have a Plano tray that I keep my upgrade cards in also, and it is a pain in the neck to dig the cards out of the compartments. I figured out a way to make it easier.

I got some rubber cylinders, about 3/4" high and the same in diameter and cut them in half. I epoxied them, flat side down, in the middle of each compartment. They keep the stack of cards from laying flat and hold one end up so they are easy to get hold of. Works great.

I would think that most anything of similar size would work.

Do you have any pics of the fit for the cards in the sideloader deck box. I'd like to see how they look inside. I'm looking for a really good solution to deck storage.

FFG needs to produce 3 ring binder pages that are made for the upgrade cards.

i have 2 dual deck boxes I use, one is side loading in each box