As others have mentioned open stock of wrenches & sockets....
Even if there's not room in the stores, it could be mighty handy if you could easily order onesie twosies as needed online for reasonable prices. Then again, Tekton does this better, with free shipping to boot. Nice Taiwanese stuff, too.
Of course, if I'm buying a single socket or wrench, it's usually because I'm in the middle of something and need it right now.
I think this was mentioned earlier, but Pittsburgh Pro made in Taiwan stubby and mid-length sockets would be nice. Sometimes "regular" isn't low enough, and sometimes "deep" is too much, you know?
The "Icon" stuff is mighty nice, but the prices are mighty high, too. For something I don't need that often, the next step down would be just ducky.