Back to the Future (Upgrading an Aged WC Rig)

So, it's that time again and I have the upgrade bug.

I've been taking a careful look at my WC rig, which is really starting to show it's age, as attached to it as I am. (It's cooling its 5th system since it got set up in 2000) There are a bunch of reasons for this. I have more money to throw at the problem than I did back in 2000, many things have changed, more options are available, so I'm looking for a bit of advice before I jump back off the deep end. The last thing that is pushing me this direction is that from all I have read it sounds like the new i7's are pushing heat loads comparable or bigger than the old 1.4 T-birds did. That combined with the probably need nowadays to cool a couple of GPU's sounds like new case/WC rig time.

Current PC:

Athlon 64 X2 3800+ (Manchester)
Epox EP-9NPA+SLI
2GB PC3200 Corsair Memory
160GB Raptor
Foo Drive 80GB
1900XT Radeon
CoolerMaster 450W PSU
Windows XP Pro

Current WC:
Chevette Heater Core
Eheim 1048 Pump with PVC Reservoir
120mm PanaFlo 38mm Fan
Antec Full Tower Case circa 2000 (3 80mm Sunon in front, 2 Antec 80mm in back, 1 90mm in back and the 120mm blowhole I cut in the top)
DangerDen Block for a 939 series Athlon
Fan Bus to keep the fan noise to a dull roar.

Where I think I'm going (approx):
i7 series CPU
4-8 GB RAM
2 Radeon 5XXX in Crossfire
Auzentech X-Fi HT 1.3
160GB Raptor
2x500GB for storage (pulled from an existing NAS)
850W PSU
Windows 7

Goals for new build: Balanced build between OC and quiet. The existing rig is louder than I would like with all those 80mm fans humming away, even with the Fan Bus.

The secondary goal here is to build the WC system for the next ten years. Something that will continue to work with me as well as the existing system has, for bigger heat loads, but that I will be able to just swap out waterblocks for whenever I upgrade.

Having read through posts here, at Extreme OC and SharkyForums, I'm guessing that I'm probably going to be looking at at least a 120.2 if not a 120.3 rig. The other option on a couple of cases looks to be a dual 120.2 rig (Antec 1200 with one internal, one external), but that will probably take a fairly honking pump.

I'm using this as my primary source of info for specific parts unless someone says it's bollocks: http://forums.extremeoverclocking.com/showthread.php?t=282232

But the starting point of all this fun will be the case. I'm planning on a tower, so I have plenty of room and this system never moves so weight isn't really a concern. Would like to keep the WC system internal to the case if at all possible, though. More than willing to case mod. I still have my 120mm hole saw. ^_^

Sorry if this is a bit disjointed, but thanks for any advice you're willing to provide.