Hey, that worked out really well for you then. At least it sounds to me like you made out. What an enormous training tool the powermeter is to!!!
There is just something about a high quality tensioned racing wheel that the full carbon wheels can't seem to match. Where I really notice the difference is at high speed and under load, like a swoopie mountain desent. The tensioned wheel talks back to you and tells you where the bikes needs to have your weight distributed while the full carbon designs I've ridden felt very dampened and didn't inspire confidence, from my perspective anyhow...
Another thing that I like about the zipp is that they're pretty friendly in cross winds (for and aero wheel).
RA40
I really like the Fisher Mendota that you've got your eye on. I looks like a very versatile bike and I especially like the geometry. I was looking at the angles and top tube length and it's very "road bike" like but with just enough touch of plushness. It has a great color scheme too.
The geometry of your old Fisher reminds me of my green trek 7000 with the long top tube and stretched out design. I sure don't miss the handling characteristics of that concept.
2000xlt
Like you stated, I see that you have hubs without rotor mounting flanges, so you're kinda stuck rotorless without getting new wheels or at least hubs. And ya know, for general riding the disc really doesn't provide many noticable advantages. V-brakes are lighter, usually quieter and provide a suprising good feel when tuned properly. We just put a set of Avid Single Digit SL's on my brother's 2004 Fuel 98 and he is very pleased with them. We did a fairly serious ride this morning with a lot of climbing and decending among big grapefruit sized rocks and he was loving his new brakes.
With regards to your low seat and high bars, often...riders prefer having their seat and bars relatively close to the same height since it improves the weight distribution so much. Although it wouldn't be possible to get them at the same height on your bike, every little bit helps. It's very easy five minute task to lower your stem some if you're willing to try a more natural riding position. Simple take the spacers which are under your stem (between the bottom of the stem and the headset) and place them on top of the stem (between the top of the stem and the stem cap). It appears that you have several spacers there...at least three or four of them and they look like 10mm spacers, which afford you some good adjustment range. You can move as many or as few as you like. The other option is the flip the stem upside down so that it doesn't rise so much. That's usually done if the moving spacers doesn't give the desired effect. If you're interested and if you should need any help, just shoot me a PM and I'll walk you through it either by PM or phone.