I still don't see a problem here. If you are satisfied with the speed of the USB drive and the fact the Fritzing (or any other application) is likely to hang if it isn't mounted, then put in the hard links pointing to your USB key and problem solved. If version skew is a concern I expect you could install Fritzing on the USB key (in a third directory) as well and run the application from there which should let you run on pretty much any machine of the same architecture (actually, no that won't work come to think of it, the hard links need to be installed on the actual target machine, but the rest should still be true). I don't think (but haven't tried it either) that it needs to be on the system disk. As to why the user directories aren't in the directory with the .exe, that gets overwritten during upgrades and they didn't want to impact the user's data. Seems a sensible choice to me. You are correct, (at least in my view) that Fritzing's most pressing current problem is more parts and the more people working on making them the better. Thus this discussion.
Peter Van Epp