Yes... this would require that I write a parser that could handle that specific query language. I had some very specific reasons for going down a SQL like path:
Easier for most to understand, as most may have seen SQL like languages before
The need to be able to scope different nested query expressions in order to isolate query behavior. This caused the creation of the EXISTS keyword in my language.
There are one or two language artifacts in the native Elasticsearch query language that would have made writing a parser impossible. To be clear, what my parser does under the covers is generate a native elastic search JSON query. The built-in query language used in Kibana is just passed to elastic search directly.
Did you consider supporting nested objects without changing query language?
e.g.
foo.nested:"abc" rather then current language
foo.nested="abc"`?