The personalized bandannas is good enough, even the movies got away with just that. Name/Letter plates on their belts would have been too far, I agree. But I'm glad they have the colored bandannas as it makes the turtles much, much, easier to identify.
And I agree that the Splinter side-story (very well draw, by the way) certainly telegraphs what the nature of this version of the characters is and it seems very interesting. Can't wait to get April introduced to our heroes.