He said he wants to go out on a high note, hopefully that means another movie on the level of Casino Royale.
That said, I'm scared that it may be too late for us to go back to a Casino Royale style movie in the Craig Era
Yeah, CR was so exciting because it was a genuinely interesting new direction for Bond, not unlike Batman Begins was for Batman. Then each sequel drifted further from that concept, to the point where you might as well replace Craig with any of his predecessors (de-aged, of course) in Skyfall and Spectre (and I did like Skyfall).
Here's hoping his fifth outing is a return to form. But I agree it may be too late.