This is an excellent write-up. I would want to vet the idea of agents being owned by the department that knows that skill/domain. In the real world, that translates to someone being—at a minimum—an AI power user. Based on my experience, this would limit the use of this type of system to the largest enterprises. Small Enterprises and Commercial-sized businesses will struggle - just like they do now to provide this resource.
The audit and manager interfaces will need to be bombproof and incredibly intuitive to work for organizations of all sizes and skill compositions.
The reusability of the agents opens an opportunity for monetization and the development of AI Agent packages. I was with a company that used this concept to drive a good amount of revenue. The OOTB agent is 50-80% template, and you need some service work to dial it in for specific flows. In theory, you could have an exchange- but most exchanges fail to achieve orbit.