You saying you got a promotion so I'm assuming you are not the leader of the guild. As you are coming on this forum with the problem, I assume your leader being one of the inactive -- or at least rarely active -- members. This usually causes an enormous crack in morale of guild members. Having a team of officers who seem to be unified by a common goal towards the members may help. This may get "bloody" however as usually you'll have a minority of officers who will simply not cooperate or listen.
If your leader is absent or fails to set such unified goal -- goal as in purpose for your guild to work towards to. Legio Romana has as goal to host at least one massive high-end PvE event in the week and recruit a minimum x-number of new members each week.

As you are calling out for help here, I'd suggest you be the strong one in the guild -- if you wish to rebuild that is -- and gather a set of officers who you can trust, who you can rely on and who are willing to work towards the goal(s) you set for the guild. Anyone not cooperating you ought to try to convince them, if not, have them demoted as they'll cripple you in your efforts.
As for assigning officers, don't import new members and promote them to officers. Solve this problem internally: round up the active members who are willing to share the burden with you. Hope this helps.