I use that case as well, elastic came out on one side so I have sewn leather and Velcro on that side in it's place. I fit 2 mods, an ego, 2 batteries, and 10 tanks, and the pouch I use for spare coils and drip tips, it goes everywhere I go.
If you dry burn your cleaned and dried coils you can get more than one use out of them, also the contact, or coil on the Davide mini may be sitting slightly higher than the rest of your attys, pull up the center pin a tiny bit in your battery and I bet it will work.