Agreed. The TCAS has other applications as well. I use it in thunderstorm flying. I look for passages that otherwise may not appear useable given my altitude, gains, tilt and range along with backdrop. One route may appear out of the question, but seeing strings of aircraft using it makes me take a second look.
I also use it to gauge if I'm closing on the aircraft ahead of me in the visual approach. One aspect of US ATC I'm not fond of is not finding out I'm behind a heavy till I check in on tower frequency. If I see excessive sep between me at super busy airports, its a good chance I'm following a heavy. I also judge if the preceding aircraft is high by watching its altitude as it crosses charted fix's, not perfect but it's one more aid.