Hi Josh,
I never used Feathers..
I have a Desktop App built in Flex/AIR.
On the last days, I did an evaluation on Haxe/OpenFl but the HaxeUI (the gui definition in XML), it's very incomplete and seems that it's not maintained for about 2 years and for that reason, I don't seem my self investing on Haxe/OpenFl.
I read all your post and comments and I read that you have a client with Flex/AIR that want to port to Haxe/OpenFl.
Do you are also considering Desktop UI ?
A suggest is to build a guide for porting a small sample project directly from Flex/AIR to Haxe/OpenFl/Feathers UI.
This would help a lot for starters (specially who don't have experience on Feathers) and seems that there are a lot of Flex Apps out there.
I really hope that you be successful and would be nice if this is a way out for Flex/AIR on Desktop, since there is not much options like there are for mobile.