Really nice work, well done. I would suggest a couple of simple changes:
Now that you are using interrupt levers, change the main levers to Aero style. Lots of low cost options out there, cable routing would be very tidy.
Get a nice alloy seat post with an integral clamp. Should be able to find one for $10 to $15.
Here's a nice Tektro set of levers, BIN now ebay, free shipping:
http://cgi.ebay.com/New-Tektro-RL340...item2311037656