If open is a empty as people claim (which isn't entirely proven since there are threads where people are crying about playing open and being attacked), it would indeed indicate that the PvE community is much larger than the PvP community, and therefore FD will probably take note of this and make some changes.
Those changes could be various.
1) They could create an official Open PvE mode to compliment an Open PvP mode.
2) Do something about PvP that means PvEers do not need to worry about being attacked if they play open. For example, a PvP choice which you can only select once on your profile or at least once per session.
3) Just forget about the PvP aspect and focus on keeping the PvE crowd happy
4) Some might say (like has been proposed here and elsewhere) that they should force everyone to play open... but those who suggested it really do not understand what they are asking for here. All i say to that is remember what happened with offline mode, and that was prior to release. Removing solo after release... nope, FD are not suicidal.
I do not think any of the above will happen, although i do hope for the official PvE mode, it would save many of us having to apply for group membership and for Mobius having to constantly accept join requests.