I understand all about gear ratios. No problems there. The more immediate issue, however, is one of practical mechanics rather than pure physics: the possibility of getting an actual chainring - with the right bcd and all, and with with money paid - only to find out after it gets here that it won't physically fit onto the existing spider or may work poorly with the rest of the bike for one reason or another. I'm sure you can understand just how big of a bummer that would be when you live halfway around the world from the source.

Another fact to consider is that, if I elect to go for a complete crankset instead, square-taper cranksets (such as this one or this one) are becoming harder to find - which means that I may need to think about swapping out a perfectly good bottom bracket for a more "modern" one for more and better crankset choices. That's both more money I'm able to spend and more involved than I would prefer!

Food for thought.