... It really only when you get to Tekki Shodan that you begin to see a real fighting kata devoted to close quarter work and are faced with a bit of a disconnect with what has gone before.
This is one of the results of shotokan being GF's attempt to meld disparate styles, I think. The Tekki kata are in themselves an excellent foundation of a "style" of karate that is almost antithetical to that defined by the foundation of the Heians. Getting the incipient brown belt (by JKA standards) to make the switch from the heian mentality to the tekki one is hard, perhaps needlessly so.
I see the Pinan and Heian Kata both as systems of close quarter fighting. There is huge overlap, what with cup and saucer, yoko empi into the hand and augmented forearm "blocks". I don't see any disconnect.