My logic is this: Firstly, they should be connected in the same order that they appear in the Node List (the Node List should be built from the Node Network). I assume that part is universally acceptable. Secondly, when I add a node to the Node List I prefer it to go to the end of the list, or after whichever node is currently selected, as with the terrain list and the shaders list. But this is probably more subjective and I don't claim that this is going to be right for everyone.