Oras all the way for Archie. Physically he seems like a more towering, virile and mighty opponent to face. His mode of dress also better represents the sea by wearing mostly blue tones, a wetsuit-inspired theme and the gold chain with the anchor design. I think Archie not only looks way better, but Team Aqua as a whole does. Shelly became absolutely gorgeous. I also think giving the characters darker tans really made their designs more striking and different from Team Magma, and also seemed plausible because they love the ocean, and might spend their time walking the beaches of the region, and turning bronze under the sun.
I would probably also vote for the Oras design on Maxie too. He manifests more of his own character in the revamp and makes a stronger contrast to Archie. Maxie has a decidedly intellectual, formal and even very stiff look with the glasses and turtleneck. I wouldn't wear this stuff, but I like that he does! He looks like an eccentric scholar who would come up with this plan to change the world, and in the process breaks the laws of fashion with the shorts, boots and long johns, just like he breaks the laws on the land. In all seriousness though, I do think it's cool how the keystone for mega Camerupt is an accent on the frames of his glasses.