Originally Posted by Tom Stormcrowe

By geometry, I mean the frame/HB setup. You aren't going to gain any speed going to the 10 speed rear drivetrain, it just gives you more narrow range options. All you'd need to change out for a full on road bike would be the handlebars and brake Lever/Shifters. You can also do this a lot cheaper with maybe a set of trekking bars as mentioned above (Bow Tie bars), to get more hand positions.

Pick up some used Brifters off of Fleabay and a set of Cane Creek bars that would fit your stem clamp and you'll be good to go. That or a set of Nitto Noodles in Silver alloy for a match. Then you'd need some bar tape.