PS if you can't tell, I've been thinking about OSM road classifications for a while, so forgive me for my hot takes/strident opinions. I actually wrote up a whole diary entry on what I learned from my efforts to reclassify roads in LA (some of which you've now reverted) here: https://www.openstreetmap.org/user/willkmis/diary/399345. Hopefully, you might find it useful, at the very least as insight into how I view things. I actually specifically mentioned FCs there as well.