This article http://old.haxe.org/ref/oop could be a reference/starting point to start with this logic node “Classes” you evok, as well as Class Instance - Haxe - The Cross-platform Toolkit when we speak about objects as instance, when using a logic node “Classes” …
(just a remark : As already discussed here Armor3d capability questions - #10 by RobDangerous, we have to deal too to offer a garbage collector help, thus as a first step with a class destructor for the management of resources / automatic garbage collection of inacessible objects and thus avoid unpredictable stalls … in this article, we have the Constructor and Initializer, but no Destructor)
I think the target to have in mind too is that OOP in Armory will be designed for the development of very large software systems.
Same thing as how to make possible to detect problems in Armory early during the design phase, before implementation starts.
When ready, we could open a new post “OOP in Armory” 
or "How to design Very Large SW in Armory)