I don't post often in these forums but this thread intrigued me.
It depends on whether Craig returns for one more on not. I agree with Tiin007 that the Craig era has caused creativity issues for EON. After Spectre, which seemed to me a half hearted attempt to wrap up the Craig era which they then backed out of, they have written themselves into a difficult corner. As I left the cinema with causal Bond fans there was confusion as to weather that was the last craig film and there wasn't much excitement for the next film. I personally am not excited by the possibility of them carrying on the Madeline or Blofeld storylines but that seems to be the only option. If Craig returns for one more they will have to commit to tying up his tenure in a way they didn't with Spectre. This should be character driven (because Craig's Bond has been and it is consistent) and one interesting angle they could explore is Madeline possibly finding herself in a compromised position like Vesper. Whereas before Bond was unable to convince Vesper that he could forgive her (hence she chooses suicide), this time Madeline who finds herself in a similar situation trusts that he can, and they walk off into the sunset together with Blofeld or whoever being dealt with along the way. This is probably too character heavy for a Bond film but for Craig, I think it fits and would be a way to tie up the Craig era.
I think there are two obvious directions moving forward creatively. One is that they return to the flat character of the early Bonds and focus on plot to drive the story. The second is that they continue to delve into the character further and use that as a means to drive the plot.
I think the audiences of today expect and crave some internal conflict within the main character. Stories are about change and the main character is usually a vehicle of that change. I think audiences would struggle if they reverted back to the flat Bond who has no internal conflict. But I also agree it becomes increasingly difficult to watch a Bond who is always at odds with himself and constantly resigning. As often in life, I think there is a middle ground which is a better option than these two alternatives.
I wrote a screenplay for a new Bond which I think (obviously!) manages to walk the line between these two pitfalls. It is a soft reboot for a new actor and uses Kenya as a location (unexplored territory with strong ties to Britain's colonial past) and delicately explores the issue of Islamic terrorism. Its in the Fan Fiction forum of this site if you are interested: The Death Collector.