I think you have covered the bases pretty well. I have found that BubbleEyes, Celestials and, to a lesser degree, Frogheads tend to be a bit more sensitive to ammonia/nitrites. It can be a bit more difficult healing a sick BubbleEye. Celestials seem to have a propensity to getting eye infections - whether from "sharp" objects or whatever.
I would recommend you make sure your tank is nicely cycled and ready to go before adding the fish. Then, ENJOY! I really enjoy my Celestial Dobbie's little funny face in my kitchen - and as I cook, she benefits from the trims of the garden veggies. She is a great "garbage disposal" for lettuce, broccoli, spinach, etc. They are charming fish - not too active, but ever so inquisitive!