So far as an FO... I've seen all kinds of captains. Some of them make the stand up PA. Some of them are really good about keeping the customers informed in a relaxed, honest, professional manner. Some of them curse like a filthy sailor in clear view of the customers in the gate area, make a rushed PA, don't keep customers in the loop, etc.
I know what kind of CA I'm going to strive to be even when everything's going wrong for us and I'm having a bad day. It goes back to the "we know you have a choice of carriers, so thanks for choosing us" type messaging... Sure the flight deck may be mostly invisible most of the time but you are one important link in the chain. You have a brand and as a legacy/major you want to protect that brand. If the applicant doesn't know what your brand is (the best soft product, the most on time arrivals, etc), is that really something that will be instilled in training? Probably not. If I ever get the call for an interview at a major, I'm going to do my absolute best to make sure I understand the culture there before I show up for the interview.