Thanks for all the input! I did not think of asking to try the XL FX1, and they didn't offer. Went to the larger shop today, and TBH, they seemed much more interested in helping me. They expect a bunch of 2022 FX3's in April, but they are going to call me as soon as they get in a bike I can test ride, maybe an FX1. They hope that might be in a month or so.

Another option might be a stagger, but the standover height of the stagger version of the FX3 is only 1.1 cm less (albeit with a more steeply sloping tube). Also now considering FX Sport Carbon 4 which looks like it might have dimensions that would be better for me, as well as Specialist Sirrus.

Bottom line, I think I'm on the right track. Hopefully I'll get to do some test rides this fall and then I'll feel more confident when the time comes to buy something in the spring. Meanwhile I'll keep hammering away on the Mongoose. Replaced the worn out tires tonight.

Thanks again, really appreciate all the constructive advice.

Mark