I'm working my way through the componentry on the tall bike, replacing and upgrading things that are worn out or obsolete. I was unable to get the existing cup-and-cone headset to adjust properly, probably because it was missing a spacer, so I decided to splurge and have Harris Cyclery in Newton install a new Chris King headset. So at this point, the key "big bearings" on the bike (headset and bottom bracket) are now high-end sealed units (Phil Wood BB and Chris King headset).
When I picked up the bike I happened to see a 68cm Rivendell Atlantis bike that was also in for service. It had a very high stem called a Nitto dirt drop. I asked if Harris had one for sale, and they did, so now I have my bars high enough and I don't have that ugly, kludgy, heavy, steel steerer extender no more!
So at this point, the only components that haven't been upgraded are the derailleurs, brakes, and wheels. The wheels are kind of a conundrum. The 126mm rear dropout spacing means that it's hard to find a good hub (although Phil Wood has one). Plus, because of my weight, a freehub would be a much better choice than a standard hub. Also, the current wheels are 630mm, while must replacements are 622mm. I'm not keen about dropping the bike by another 4mm, given the long 185mm cranks.
Or should I get a new bike? I love the look of the Rivendell Atlantis, which is available in a 68cm size. Or I could get Mike Flanigan to build me a custom. Or I could do the Peter Cole thing and get a used 68cm Cannondale touring frame.