New P2 and I am only interested in things that make the bike go faster when I pedal it. I have a good fit and already think the bike looks pretty good so cooler looking aerobars, cockpit, etc don't matter to me unless they result in me having a faster bike split. Right now I have a 2011 circa set of Zipp 404s with an aerocover, a darkspeedworks 483D speedpack for spare tube and c02, keomax pedals and a Lazer Tardiz helmet for racing. I run Continental 4000s ii tires but am not currently running latex tubes because while it seem that they are a bit faster, the risk-reward with flats and delicacy of care makes that less attractive to me. I open to all ideas but was thinking mostly about what I could do the drivetrain (ceramic parts, different chain and/or cassette, Di2 or otherwise upgraded derailleurs and/or brakes, etc) that would make it faster and trying to figure how much faster it would be for how much cost (ie $1000 for 20 second not so much, $500 for 1-2 minutes is more interesting).

Well then I would read one of the many threads on aeroness/bang for your buck etc. there is nothing unique about a NP2 that upgrades for it would be any different than upgrades on other bikes. It sounds like you already have most pure bike upgrades (as opposed to helmet, clothes etc) covered except maybe cockpit which you can read about as much as you want on here. My personal experience was a "faster" cockpit wasn't faster because it was uncomfortable and put me in a less powerful position I couldn't hold but most riders would get faster with a Tririg or the like.

Tri-rig front brake? That's all I can think of from what you've described.

I was aware this is true for some models (like my old P4 with the built in water bottle) but wasn't aware this applied to the P2. And to the OP.....do yourself a favor and use latex tubes. Have your lbs install if you are worried about correct installation.....there is no need to worry about an increased chance of flats.

A better bet is aero neutral *if* you get the right bottle.