The Dyer and Ling list suggests that 25 to 30 cm of aperture are required to see NGC 609, and 30 cm for NGC 7822. I used 15 cm, so perhaps the recommended apertures should be taken with a grain of salt. On to double stars. Seeing was in and out, and position dependent, but with a little work I was able to work to well under an arc-second of separation, at least for stars of comparable brightness. Sometimes the most interesting doubles are of differing magnitudes, though.
Some stars are of interest for color.
It is easy in much less aperture than six inches, and to my eye is red and blue, as impressive as Albireo though not nearly as bright. It belongs on your list of showpiece stuff to impress mundanes with. As I said, I don't mind slumming. I have been doing a Messier survey with this instrument, and picked up another dozen or so objects, all at 24x with a nice Kellner eyepiece. The double star that is M40 was easily resolved.