Use the Songs view where the check marks are visible.
Use iTunes Feedback to say you'd like the greyed out visual cue for unchecked songs restored in other views.
FWIW, checked/unchecked status is not the ideal way to manage device content. It limits you to managing one device (or several clones) and prevents regular playback of content in your library which isn't currently selected to sync. Make one or more playlists to sync with each device and, in general, leave everything checked. The unchecked tracks in my library are things like bonus interview tracks that I would never want to hear at random or even when playing the album straight through, but which I keep in my library should the mood occasionally take me.
tt2