I'm gonna post before you get overflowed with "admins are volunteers, fak u asshole!11!11 WE HAVE LIVES XD", there is basically no solution for us to get more active admins other than either..
1. Making receiving SA easier (which we already practically have).
or
2. Adding Incentive for admins (which if you have a reasonable idea I'm sure it'll get looked at). The incentive for administrating is supposed to be helping the server but as I've found out since I got back a lot of people just want the rank to swing their dick around which is pretty obnoxious.
I don't know if you already have me added but feel free to call me on when you get the chance and try to encourage some of our good, mature, active members to apply for admin. I think this problem is smallest where PB is concerned currently, which in perspective is pretty sad considering how few admins there is at times.