Then what you should do, if one of your worlds was in jeopardy of contraction -- had lots of openings that weren't filling -- would be to assist the commish in filling the remaining spots with quality owners.
If there's the potential for 30 or so worlds that are at risk of contraction, make sure yours isn't #27, #28, #29 or #30.
The worlds which don't fill, and which don't have a core of veteran owners willing to go the extra mile to get them filled, should logically be the ones to contract first. They would have the least # of owners who cared about the long-term future of that world, right?