I'd definitely hold onto the chaos legion cards for a while before selling any of them. If you can wait for a while that gold foil Djinn Inferni will be worth way more in the future once the CL packs have been sold out for a while.
I'm really liking these new summoners too, I think they're fitting in nicely with the past editions and should be some of the most used summoners for a long time.
I've just been selling cards now because I'm trying to get more value via the airdrop than the cards. I was actually considering the cancelling my GF for sale but It was just sold an hour ago xD Oh well, hopefully I get a new one soon!