What a beautiful job! Love the wood color, and the rustic look...very cool.
Faucets: Perlicks, no question. Don't forget to pair those with a stainless steel shank. I'd also recommend a 90 degree tailpiece.
Beer Line: 10' x 3 of 3/16" (the longer length will enable you to serve at higher PSI for those higher carbonated beers)
Air Line: 1/4" thickness, length depends on your build but probably 4' for each keg. It's a bit tight on some tailpiece connections, but just use some keg lube and/or a lighter. The only way to get it off after that is to cut it off, and you won't have to worry about leaks EVER.
Regulator: Double pressure regulator, I like Micromatic. It's more spendy for the dual pressure reg, but worth it in the long run. It will be less hassle to carbonate your beers, and more enjoyable in the long run.
CO2 Tank: I started with a 10# which is fine, until I saw how much it was to fill up a 20#. It's only about $4 more for me to fill a 20# than a 10#, most of the cost is in the filling fee and hazmat. After filling it 3-4 times, you'll have paid for the extra cost of the big tank...plus you only have to fill it 1-2 times per year. Also, whatever size you get, just leave it outside the keezer and drill a small hole for your air line in the collar. The added space is great, plus it helps with the line clutter.
Manifold: a 3-way manifold for the serving pressure side would be perfect for this setup. I prefer the aluminum block ones to the brass ones, but it doesn't really matter so much since it's hidden.
Drip Tray: Best price I've seen is this 19" stainless drip tray from BarProducts.com. Great construction, and costs just $16 before tax and shipping. Nice solid build quality, and the cheapest by far.
http://www.barproducts.com