I agree racer38. His maximum power is about all that can be expected, perhaps two or three more at the most without any more major work. I think the OP is concerned (or I am, atleast) with the flat spot at 10,000 rpm, and the lack of over-rev. My MC21 happily revs past 12,000 rpm to 13,000 rpm. Granted his is an MC28, but it still should be making power after 11,500 rpm unless the dyno operator is closing the throttle?
The power doesn't look smooth, either. I'd say some careful jetting should sort it out.