I know weight really doesnt matter when it comes to tri performance, but do what makes you happy.
So heres some ideas based on what you got planned:
drop the zipp skewers and get the control tech non QR, you wanna lose 1/2 lb-3/4 lb and a lb is 454 grams---the non QR will give a reduction of like 40+ gms.
get rid of your heavy DA cranks
do the HED3s have ti axles----you can pick these up pretty cheap on bicycles marketplace newsgroup from kristan roberge, i have.
every bolt needs to be ti, like if the stem doesnt come with them, top cap, seat post, etc. you can contact srp-racing and they can provide you with any ti bolt you need practically, just give them the size you need.
ti BB will lighten you up a bit too.
Theres a 13 gram bottle cage on EBAY right now---you can get away with almost 3 for the weight of your zipp.
What bike computer are you using? If you use a polar bike computer, you get away with two for one---and it doesnt "weigh" your bike down as much as a normal pc.
Dont pad the ends of your aerobars, really its not necessary. Heck dont pad the pursuit bars either, wear thicker gel gloves in training.
Want: 58cm Cervelo Soloist. PM me if you have one to sell
Vintage Cervelo: A Resource