Hi Jonathan, imho LCD 3 tops your list but they are open ended and twice more expensive than the Omnis which come next. Over the years I gradually moved to closed end HPs, finding their sound to be more cohesive and accurate. The one area however they give ground to the top open cans is spaciousness, depth and width of the sound stage. Granted, top closed models such as the Omnis, Alpha Prime and XC narrow it very much, still a top open can will be more 'open' than a top closed one. I presently own Omni Walnut, Alpha Prime and LFF Enigma, and the latter stands above them all including LCD 3. To my ears the Primes are more resolving than the Omnis with a less prominent lows but a bit more detailed. Soundstage is about the same, though the Primes feel slightly more open on some recordings due to extra details in the highs. The Omnis are more fun to listen to in general, being ever so slightly darker overall which tend to make music more exciting, and they look much, much better than the Primes (which is important too). The Enigmas on the other hand combine the details of the Primes, with the slight darkness of the Omnis - detailed yet prominent lows - and the openness of LCD 3, yes it's true. From your list though I'd go for the Omnis unless openness is a top priority/must and you can splash on LCD 3.
