Since REST uses standard HTTP it is much simpler in just about ever way. Creating clients, developing APIs, the documentation is much easier to understand and there aren’t very many things that REST doesn’t do easier/better than SOAP.
REST permits many different data formats where as SOAP only permits XML. While this may seem like it adds complexity to REST because you need to handle multiple formats, in my experience it has actually been quite beneficial. JSON usually is a better fit for data and parses much faster. REST allows better support for browser clients due to it’s support for JSON.
REST has better performance and scalability. REST reads can be cached, SOAP based reads cannot be cached.
With IoT devices gaining popularity making use of REST comes almost out of the box with every framework nowdays. If you also do MicroServices, Domain Driven Design, Modular Design you will find REST to be the best choice.
I personally am very thrilled about the REST API and I dont run my WebApps on Windows but rather on Linux with nginx/apache so I dont have to try and deal with somehow knowing about .dll’s of Epicor by using REST. If you decide to change the logic of a BO you will still probably offer API versioning and you wont break my Web Apps, Mobile Apps if I use the REST API which is another win.
Lastly, since you guys utilized OData you have a solid foundation.