After posting I remembered this helpful post from Jim:
This helps a little – I mean I can see how Can/Can’t fits with Want and maybe even Won’t. (“You can’t, or you won’t?” mother said knowingly.) Maybe I need to focus on that for a bit.
I can almost see a Need-Should axis too now …
I think perhaps the axes I was seeing (Need vs. Want, Can vs. Should) are the more simplistic, face value type of conflict, but the Dramatica model is zeroing in on something that’s a lot deeper. Fascinating!