Thanks for your feedback.
I was aware of the library you mentioned, however by using extensively Neo4j in production at several customers I had never the need to implement this kind of Cypher wrapper.
The Rest API is really powerful, you can manage transactions like you would do with any native driver and it implements streaming. The main concern right now is that the API Response is really verbose so if you fetch 1000 nodes you have a really big json back while generally you will implement lazy loading at this stage.
There is some work on Neo4j internals for a new api protocol (SBE) which is far lot faster than JSON while JSON will still be supported.