Interesting. I didn’t see that game. If I had to guess, I’d have said she’s a good defensive match for Caroline simply because she’s strong and neither one is super quick. Caroline relies on strength and footwork to muscle past smaller guards, which won’t work as well against Ayanna. But I suspect she’s not going to be able to guard quicker wings as effectively, and probably not against quicker shooting guards.
By contrast, Aubrey at her best two years ago could defend shooting guards effectively. For example, she was able to cover Caitlin Clark and Dijonnai Carrington. She even was able to cover Zia Cooke effectively. This was only for brief stretches, to be sure, and Aubrey is not as big as Ayanna. But she was quite a bit quicker and this matters against players like this.
I think the ceiling is very high for Ayanna for the reasons you cite, even if I don’t think she’s going to be quite as versatile on D as you seem to. For one thing, I suspect she’ll have better offensive skills than Aubrey.
Thinking strategically, however, I picture Ayanna as a serious defensive contributor against SC, where she should be able to shut down Saxton. One of the elements of SC’s attack is a quick front line in Boston and Saxton. I don’t imagine we’ll be able to outplay Boston. But they depend on Saxton, a strong 4 who thrives on rebounding and putbacks. If Ayanna takes that away, I suspect Boston won’t be able to defeat us even if she has a great game. Ayanna is bigger, stronger and quicker than Saxton, and they don’t typically face teams with that much strength and speed on the front line. If Ayanna can shut down Saxton come tournament time, she’ll have done more than enough to earn her spot in the lineup.
If Ayanna can spell Caroline and Lou at the 3 occasionally, I think that will be useful. But I don’t think it’s a lineup we’ll want for long stretches of a game. That would be like putting Aaliyah at the 3. We’ve done that when we had to — watch the UCLA game to see an example — and it came with severe costs against a quick team.