I think if they used the ability to swap classes on the fly like they did in the Shb trailer and fudge the abilities like they normally do, like how DRG can't jump several times while already in the air but it sure looks cool, we could see DoM in a trailer and it would look good.

Our allies on the ground from a super colossus, WoL walks up as a WHM heals them all, the colossus rushes us and swings its massive sword, we hot swap to SCH, block it's attack with a barrier as we're sent flying and bounce off the ground, Eos heals us as we get up, only for the colossus to send a huge energy wave from it's sword at us, swap to AST, block it with a huge barrier and we're covered in smoke. Suddenly the colossus is hit by several FireV's and a flare revealing we swapped to BLM in the smoke, damaged it launches missiles at us and we quickly swap to RDM dodging them before quickly casting jolt, dodging more missiles and then dropping an instant verholy taking out one of it's arms before leaping onto it's head and stabbing it in the eye, before it can grab us we kick flip off of it high into the air, swapping to SMN and summoning Demi-Bahamut who's shoulder we land on as it mega-flares and finally finishes the coloussus off.

Something like that would still give the motion and speed they seem to like in the trailers while letting the DoM classes take the stage.