I personally don't think there is enough time left in this season to be certain that Lindy and/or Aho are ready to be full time, effective centers at the NHL level. And Necas is an unknown until he does it over here. If the right opportunity presents itself, get a top line center at the deadline/offseason. We know for a fact that Lindy and Aho are just fine at wing, and that in general, many centers can shift to wing and be somewhat effective. Worst case, you end up with too many effective centers and get to choose which ones you most want to keep, which ones are the best value, and potentially trade the others for whatever the need is then.
Granted, if we lose out on all potential center signings or trades, of course there's no problem with going for a high end winger, but I think the goal should still be a big time center.