All valid points.
My opinion is that characters like Kenobi shouldn't be cheapened by appearing in stuff like Rebels. Again, only my opinion, but what's the point of hiding from the empire and protecting the son of Vader if he's just going to come out of hiding for whatever reason when he's called upon. It worked for EpIV because Leia was asking for his help, and the force brought Luke and Obi-Wan together. It was destiny.
I don't know how the story for Rebels is going to be written to fit Kenobi in it, so all this is speculation of course. It may be written very well.
I also have to remember through all this, that anything Star Wars that comes out post 1999 isn't for my generation of Star Wars fans. It's for the kids.