He may stay in a PJ Tucker role in the Spurs themselves, specially if the market is rather dry for him, and specially if Manu retires bc the Spurs will have wing bench minutes available. I would rather Danny gets them than Bryn Forbes for exmaple, but frankly Danny must be looking for his last big check and he knows the Spurs have had a wondering eye when it comes to trading him.
I think the team indeed needs some refreshing anyways. Danny is not where I would have started. Consider Pau Gasol in the team, how much he's getting and yet the minutes he's getting right now. But they have to start somewhere.
Ultimately this one is tough to predict, but like you I tend to think he's not coming back.