When you add field permissions to some fields, you can’t see which ones have them and which don’t. Unless I am missing something of course. It would be useful to have a little icon (like for sync’ed fields) near the field name.
Now, only if you set field permissions to “nobody”, you see a little icon next to the first record if you select the field. Not useful having to click through every field. For other options, you don’t see anything.