I have participated in several Eve-side fleets to provide Orbital Bombardment opportunities to Dust players. I've provided OB support in 100 man fleets, and I've been the only pilot in orbit. None of my OB fleets were contested by the enemy and for good reason because;

Orbital Bombardments don't matter

In its current implementation, Orbital bombardments are earned just like Precision strikes; 2500 War Points earned by a squad. Sure, they are supposedly more powerful, but counter this with the fact that Precision strikes are near instantaneous, while OB's are subject to the EVE players and lag.

This usually means that the EVE fleet above waits 20 - 30 minutes to launch 1 - 3 strikes (maybe more if you are point-whoring in a tank.) Eve players get no killmails from OB, are bored out of their minds waiting, only a few players are even marginally rewarded with the opportunity to OB, and meanwhile the whole fleet has to deal with the risk of getting and staying in position. While DUST players on the ground have to choose between an instantaneous PS or a laggy OB.

To recap: There is no need for DUST Corps to have air superiority. And there is no incentive for EVE pilots to go provide air support.

A solution for this would be to implement the same OB system we saw during the fanfest tournament: OB's available every 20 - 30 seconds to the Alliance who obtains air superiority. This would incentivize both DUST and EVE players to compete for the space above a DUST battle, because air superiority would provide an incredible resource edge. This is balanced by the fact that DUST players cannot indiscriminately call in OBs (like in pup matches) because in Planetary Conquest, friendly fire is on.

I think 20 to 30 seconds might be too often, and I say that as a member of an alliance that has absolutely no trouble keeping space superiority. The basic idea is sound though. We've had several fights where fleets formed up and were unable to drop strikes at all due to technical problems etc. They have to use a jump clone to get to the region, and that means they have a 24 hour period where they aren't available for srs bsns fleets in null. On top of that they wind up bored from not being able to do much of anything. Even if the fight goes like it normally would they'll only get to drop a couple strikes. I wouldn't be surprised if they just stopped showing up.