Right now the IClient Node interaction is defined by the API ISearch. Though this is very limited. This api is very focused on search. Does not give users the ability to programaticaly create Lucene Query Objects and we always expect HitsMapWritable.
The idea is to generalize this api so it can be used for more than just search, but content look up (cached pages, facet search etc). We could have a simple Response request(Request) method and encode the kind of requests into the request object. Since the lucene query object is serializable it should be easy to write a writable request object that transport all sorts including a lucene query.