Michael, Here are my thoughts on where you would benifit.
911 T Struts:
* Vented rotors
* Brembo Calipers would be about 5lbs lighter "each" than the 320i (same pads etc. just not cast iron pigs)
Regarding the rest:
* SS liners - In my almost 10 years of building (thousands of) calipers, I've never seen the need to sleeve an ATE caliper, and that would make for no performance difference... just a lighter wallet.
* Adjustable valve - Stock bias is set by the calipers with "Full Flow" going to the rears. An adjustable valve will only make this worse by further limiting fluid to the rears (unless run wide open so... why get an adjustable valve?). This is compounded by the larger 48mm pistons you now have up front. So... Heavy front bias now and a valve that further limits the fluid to the rears. If you no longer have the stock pressure regulator, you are endanger of locking your rears up in a panic stop (unless your bias valve has basically taken them out of the equation... that being the case, you're missing 30% of your daily effective stopping power). You really need a valve that controls the amount of fluid to the fronts...
* Rear Calipers - I would be on the hunt for 914-6 rear calipers or Ferrari Dino/308 rear calipers. Believe it or not, the Ferrari versions can be less expensive. Early Dino's are the same as 914-6, Later 308's need a bleeder mod. This would give you a proper 38mm piston to re-balance your bias to factory specs and a larger AP31 pad size.
* Various other suspension bits - All good stuff from what I see but won't factor much into brake bias.
* Further gains can be made by changing to a 911 or 944 rear drive system with the better CV's for your V8 application. Read through that 5-lug thread I posted the link to. (suggestion made by guessing that you have redrilled 914-4 hubs and stock 914 CV's... coule be wrong. Assumption based upon redrilled 914-4 rotors etc.)
Hope that helps.
E.
P.S. Check your stainless lines often. If they go, they tend to take you with them.