So now that I'm back from Rome I've bit the bullet and revised the drivetrain on my Tikit. Here's the rundown of options:

• The baseline tikit has 349x37 tires, a 53T chainring, and an 8-speed 11-28. Sheldon says this comes to 31.2 -- 79.4 gear inches. Not fantastic.
  
• Upgrading to Scorcher TRs (about $80 for the pair), at 349x40, brought me to 32.0 -- 81.3.
  
• Upgrading to Capreo + Scorchers brings us to 34.4 -- 99.4, a significant loss on the low end but a great high end. However this is an expensive proposition. A Capreo installation involves upgrading to 9 speed shifters, a wheel rebuild, a new hub, a new chain, and a Capreo cassette. This is easily $350 in parts and labor. And Capreo cassettes, whose small cogs wear out fast, are a good twice the price of an ordinary 11-32. And Capreos are... scarce and likely to get scarcer. This nags at me.
  
• Upgrading to an IGH + Scorchers. I could get roughly the same gear inches as a Capreo with a hub, but they are even more expensive. And I have vertical rear dropouts, necessitating a tensioner which sort of negates the whole elegant point of an IGH. And as I've mentioned in an earlier post, though they notionally don't break down often, it seems to me that IGHs are even more problematic than Capreo when they do break down: not many shops can repair them, and I certainly can't.
  
• Upgrading to Dual Drive + Scorchers. Basically a 3-speed IGH plus a cassette. There are people who swear by Dual Drive, not the least of which because it's got an amazing range (19.2 -- 110.6!!!). But to me it seems like it combines the worst features of everything: it's got more things to break, it's got the difficulty in repair that comes with an IGH, it's got the grime and inelegance of a derailleur setup, it's got even more custom stuff, including its own special shifters and click box, and it's got about the same cost as bigger-geared IGH. It's fragile. It's not cheap. And it's less efficient than everything else. So I dunno.
  
• [EDIT]Upgrading to Schlumpf SpeedDrive, existing 53T chainring, and Scorchers. This bit of awesomeness would bump things to 29.1 -- 131.01, so high that it'd probably be worth having a smaller chainring. But now we're talking a lot of money: at least $500 plus labor, including chamfering out the bottom bracket.

So I've decided to go with the cheapest, most straightforward option:

• A 60T front chainring (the biggest the Tikit can take), plus an 11-32 9-speed in the back, plus the Scorchers. Requires a new cassette, new chainring, new chain, and new shifter. Because I'm doing 11-32 rather than 11-28 (so I maintain about the same bottom end), I'll need a new derailleur too. And it's nearly impossible to get a chainring guard at that size. And I'll look ridiculous. BUT the cassettes are standard and plentiful, the total cost is cheaper than anything else, it's easily and cheaply repaired and replaced. Gear inches: 31.7 -- 92.1. Not horrible. 11-34 would put me at 29.8 -- 92.1.

Where I've heard about 60T chainguards: (1) I'm told Sugino at one point sold them, (2) Bike Friday will make them but they're costly, (3) Toxy sells them for $50 apiece, and Greenspeed was selling some old ones for $2 apiece (!!!) in October, but someone bought their entire stock, and new ones are $60. That's the extent of my internet scouring and phone-calling. Other leads are welcome.

Last, I'd been hunting for front derailleur options. All I'd found were (1) Braze-on derailleurs, such as found on the Speeding Tikit, and (2) the odd front derailleur mount job in Taiwan that connected to the seatmast latch plate. Oh well.

Am also installing an old-style seatpost to enable my $1 Brooks, and looking at some North-road handlebars which won't make the folded size much wider. Maybe a few other gizmos too.