Hey Andrew,

I was on holidays, so with a bit of delay answering your question :)

Yes Ecotone is like Prooph with additional features.

It overlaps funcionalities of Prooph Service Bus, and make use of Prooph Event Store for Event Sourcing package.

However those are high level features and on the bottom it provides Messaging Framework for full message flow in your system, no matter if it's monolith or microservice architecture.