Retail locations would be terrific, but sadly won't see many in the new future. Who would want to go to the expense of opening a store-front business, while the FDA and local governments are talking banning e-cigs.
In the meantime I would recommend having backups, and backups for your backups.....build up your stock every time there is a good sale, slowly, as much as is easily affordable. (you would have spent it on analogs anyway)
For a backup, I went with entirely different batteries, charger, and adapters to fit any atty / carto to any of my batteries, or PVs, or PT. This way if there is a catastrophic failure (dog used charger for a chew toy, charger goes bad and takes all my batteries with it, etc....) I have a true backup system. Any backup worth the name needs to have a backup for each vulnerable sub-section, power source (battery or PT), actual PV (mod or ego, etc), atty or carto, and plenty of juice. IMHO
I use a PV-1 for my main vape, ego system backup, 510-system back/backup, pass-thru, back/back/backup, with adapters to fit any combination of power to juice, chargers and backup chargers.
I will never smoke an analog for want of a good vape.