We used to have more control, but I think it's part of the algorithm-driven nature that Airbnb has implemented such that your pool photos show up as the main listing photo when someone searches for "pool" or piano photos when someone searches for "piano."
It's a nice concept in theory: that algorithms driven by the searching habits of thousands of users know better than the hosts themselves. Unfortunately, in practice it doesn't often play out the way the perfect use-cases project. (Houses 20 miles from a ski park are listed as "ski-in ski-out" because they've included photos of that ski park as a local attraction) ... And who knows how the more "mundane" listings will present, which unfortunately is the majority of our listings.
In short, I don't know the answers and I agree that the interface leaves something to be desired. And as a host who worked hard to cultivate my photos in an order following the layout of the home and the most common amenities mentioned in reviews, I feel your pain. Yes, VRBO seems to trust the judgement of hosts much more and interestingly, we've been getting many more bookings through that platform than through Airbnb since the migration to the "algorithm-driven" back end.