A-tin is mostly to be used as a spy, not really on the team at all, more just a contact. F-tin would be useful, I'll admit.
It's not unreasonable to think that by this time, people would have figured out (as practice is gained via more available metal) how to anchor Connection tapping to people, which has been hinted as possible, increasing your ability to convince them. Also speeds along negotiations if they're viable, since you can artificially establish a connection that normally takes psychologists weeks to do.