I can't for the life of me figure out where the 12-2 wire goes. It's tied-in to the receptical and runs out of that box. I'm tempted to just tie it off, but don't want to have to tear things apart later when I discover what it's for. The breaker is 20A. I'm thinking I would just add a 10-3 extension onto the existing 10-3, add a 12-2 extension onto the existing 12-2, run them both into the new box and then hook them up as they are now (i.e. blacks tied together, whites on the receptical terminals and red to the terminal). That sound like a suitable way to get it hooked up?

Wire stretchers are available from purveyors of left-handed monkey wrenches and smoke shifters for the grill. All 120 V splices and connections must be enclosed. Exposed low voltage wiring does NOT have to be enclosed. Can you put a small LV power supply (AKA 'solid state transformer) near the back and run low voltage wiring to lights at the front?

I do agree that it looks a bit high, and usually start around the 30" mark when possible. It depends on the chandelier itself, and you never want to hang too low if it's a wide piece for fear of bumping heads! I don't have advice on how to rewire/add length other than consult an electrician, but if you add taller chairs and a tall centerpiece, that could help with the disconnect. Try a cluster of tall/varied height candlesticks or vases in the same color/finish, and maybe add a runner to complete the look. Good luck!

The fixture can be purchased with additional chain, however the priority is actually do you have enough wire. chain can be added toward the top, even if it is not a perfect match it would be too hard to see. worry about the wire first.