I have had saddled air cells, detached air cells, and air cells that were nearly on the side of the egg, sometimes the air cells start to correct themselves as the chicks grow but even if they don't I hatch all of the eggs on their sides. Normally they don't need assistance but I have had one or two that needed a little assist. I don't know that hatching them vertically would have made a difference though.
I'm incubating a peafowl egg right now with a completely free floating air cell. It moves around like a bubble, I've never seen one this loose before. I still plan on hatching on its side though. I think it's a personal preference, I haven't lost a single chick from hatching horizontal. I just always make sure that the air cell side is facing up in the incubator for the chick to get into position for hatch. I'm not sure if that's helpful for your situation, but that's my experience!