HGSS>ORAS>FRLG>BDSP
HGSS was a great reimagining of the Johto region, the towns felt more unique, you got some features that were intended in the originals readded, some nice extras like the Poketriathlon, and even the Battle Frontier (though it's a copy of Platinum's). Its biggest problem is that the level curve is still pretty awful, but it's not enough to put ORAS over it.
ORAS is next, like HGSS it's a good reimagining of Hoenn as it expands and fixes many of the story flaws, adds some new and improved features like the DexNav and Soaring, and has some nice extras like the Legendary hunts. The only issue is that it ignores Emerald content aside from the Delta Episode (which is a mixed bag on its own for me), and it's not just the Battle Frontier, it's also minor additions like the improved Gym Rosters that I missed. If it had that it'd probably beat HGSS for me, but without it falls short.
FRLG is a copy paste aside from the post-game, it's nice to have the Sevii Islands and the QoL improvements to the gameplay, but I don't like that they made the main story so 1:1 with the originals aside from a brief detour.
BDSP is faithful to a fault. It is nice to have the improved rematches and the Underground, but it doesn't make up for the almost complete lack of Platinum content (which IMO, did so much to bring up Sinnoh as a whole) and the lack of general improvements in other areas.