The reason you feel like there is a lack of active moderation is because there just isn't much to moderate. The subreddit is the quietest it's ever been in the almost 2 years that I've been a mod. That's just what happens between album cycles when nothing is really going on with the band. Because of that, there isn't really a desperate need for a new mod right now, there wouldn't be much for a fourth mod to contribute towards. I think when the next album cycle starts up and the subreddit starts to blow up again we will seriously consider bringing on a new mod. You made some great suggestions for who would make a great mod though, which I definitely appreciate and will likely come back to when the time is right!
As far as discussion and things like that go, I definitely wish I was as active as on here as I was a few months ago, but it's been a busy summer for me and I know it's the same for the other mods. But I check the subreddit several times a day to make sure things are always looking good, so you have nothing to worry about in that area.
If anyone has any suggestions for ways to spice up the subreddit and make things more active then us mods are always all-ears!