Nice hearing from you. We are indeed moving to COUNTER R3, and we're also planning on having COUNTER stats (among others, eventually) retrievable via SUSHI. See this list of bug reports
for a fairly comprehensive overview of what we're working on. Some of this will be available in OJS 2.3.2 (we're going into release testing soon).
However, I'll stress that we've largely been developing this support somewhat in the black -- we understand how the report and SUSHI protocol are supposed to work thanks to the documentation, but we don't have any actual use cases ourselves to test against, particularly with respect to usability and completeness. Is there any chance you would be willing and able to help us test these features with a journal or two? It'd be the best way to ensure that COUNTER functionality works as expected for your journals.