I love connecting with pastors outside of service times. It's a chance to witness someone being authentic and not putting on a show. That's not to say they're perfect, as the skeleton in their closet is probably no bigger or smaller than my own. There is simply always something new to be gained from these conversations.
I often hear the importance of mentoring. I acknowledge the value and necessity of it. The challenge I find is "how" does one start this type of relationship. A pastor doesn't really have a choice of who his flock is going to be; if it's a youth pastor, it's whoever attends the youth group that evening - same with young adults or Sunday services.
Don't overlook the older generation. I think that in large churches people have a tendency to huddle with those of similar age. That's fine, so long as you do not exclude yourself to just that one group. This is an advantage I see of small churches, where everyone is mixed into one group and the opportunity to interact with people of different life seasons is more organic than forced.
I wonder how much onus both the mentor and the mentee have in attaining and then retaining a mentoring relationship.