This has been discussed over and over on both VAMM1 and VAMM2 discussion threads. I've suggested people to send me serious libraries, none of them ever did it. And the amount of people with the skillset or patience to do that is so minimal that my time is better spent elsewhere on my plugins.
The VA system is not tied to the arousal system as it makes no sense. When Excite will be available, it will be a way to control VA based on the arousal.
So that you don't misunderstand me, I'm never against suggestions and ideas. As most of my plugins and discussions show. But I'm also pragmatic and I prefer to work on things that benefit a lot of use case/creators or even simpler, my needs. When I'm spending time doing something for 3 persons, which will probably be used in 2 scenes over 3 years... i'm not spending time on things that will be used widely for every possible scene.
If there is no other solid voice plugin, with serious features and excellent voices, there's a clear reason behind that: money/means and time/knowledge. The moment people see the INSANE amount of time you have to spend to make a voice great, they pretty much drop the ball. And this, with just the VAMM1 complexity. With VAMM2 and it's average 500 to 2000 files per voice, it's even worst.
If there's any "user customizable voice" in the future, it might only be on VAM 2. And I'm saying "might"... not will