What I would really like to see is transparent overlays with land ownership boundaries, so I would know if I’m on BLM, forest service, NPS, or private land, roads, and trails of course, and then guidance on what users can use the trails ie.

Map errors are often quite significant, often measured in hundreds of yards. Garmins 24k Topo is better trail wise than most products out there right now, but not nearly accurate enough for routing to where you can count on it to let you know you’re off course. The option you describe is probably about as good as it gets. In Capitol Reef cairns are all you've got. Just wish I could get the darn thing to beep when I've missed a cairn. I've been compiling those for myself for a while, and just started to make routable ones using my own tracks or tracks from OSM when mkgmap (OSM routable compiler) became available. It sounds like a reasonable alternative would be CNNA NT with transparent Topo and trails as a separate overlaid map. Water features, poi locations etc tends to be much more accurate than the 1:100k maps. The street data is very good, but it it's not as up to date as the latest CN version. More and more though you can get good data for areas you're interested in from other GPS users though. I've yet to find any maps that are very good for trail, or OHV routes yet. Myself, I don't use routing on trails, and I make double sure I'm not locked to road so the unit doesn't alter my track data should it be following a trail that isn't accurately drawn. Routing on trails you get the same beeps etc as you get when routing on a road.

Sometimes it shows dirt roads as trails, sometimes the trail data is ancient, sometimes it's quite modern and accurate. I've found that the 24k topo for the Southwest has quite a few trails, although they aren't necessarily that accurate.

Used garmin topo us 24k southeast cd