......
Am I missing something?
No you're not. I looked at the geometry and thought it might be wrong but it's always worth a double check. The Thorn is, in many ways, slightly old school, with a longer reach.
Reach is obviously key and on a smaller frame, frame angles are probably a number of compromises to do with reach, handling and clearances, with a nod to a sportier ride or a more stable ride, in which chainstay length, wheelbase and rake/trail are all going to play a part. Sometimes it's as well to step back, trust the designers and read the description.
This thread peaked my curiosity but after a whole bunch of googling I can't find anything other than what has been suggested in a steel frame. MacB said it earlier, short of a custom build, for which Hewitt and Roberts amongst others, spring to mind, I'm struggling to think of anything with the right dimensions. Roberts built Josie Dew's bike and she isn't tall.
The
Condor, Surly and the Specialized, RecordAce linked to are pretty much all that's come out, oh and that Jamis. The Specialized you can't get in this country, which may not be an issue for you, there was a thread about it a long time ago (do a search on here). Spacycles are selling the Pacer frame by the way.
I know you said steel and I know I said it before but if you can't find anything that suits, Kinesis frames are well thought of. Of course there are a lot more ali frames than steel so it won't be the only one. Beyond that, I agree with MacB, it's summary and decision time, unless someone can find another to throw in, personally, I can't.