First, I hope you saw Tim Kaine in Miami. He did talk some about himself. You would have gotten a sense what those of us who know him here in Virginia have known about him. If you didn’t see it, look to find the video of the event and watch both Clinton and Kaine.
Perhaps I can offer a bit more
Back in June Sen. Kaine was interviewed on C-Span for American Profiles. The show was being replayed leading into event in Miami introducing him as part of the team. My wife and I watched it, and while it runs more than 40 minutes, it is well worth your time to watch it.
Here’s the link for the video (having trouble getting it to embed)
If you go to link down along the left there a number of markers so you can if you choose jump to specific topics