Well, seems it's been awhile since I really thought enough about it to put it into some form of a "list". Something about that approach just doesn't sit well with me - maybe it's reminiscent of building walls rather than doorways ?
But other than the obvious ones you listed it seems that a few that I'd have to have on that list would be....
Connection to nature
Full embracing of sexuality in all it's forms
There's probably a few more if I were to think on it.
As to when a relationship is "successful" - that's pretty easy for me.
It's successful when it's flowing like a stream - bubbling it's way over the rocks & bumps it encounters and finding it's own way around obstacles in it's path. Effortlessly moving along, singing.