Rather than colour code my heddles, I wrote the number of the shaft on the shaft. With the AVL this is possible, although not all looms are 'equal'. :) I routinely shift heddles from shaft to shaft, depending on weave structure and epi. But each person/loom is different.
Yes, it would depend on the weave structure. An overshot is often just written out with only the pattern sheds shown in the treadling, generally with a notation to 'use tabby'. Plain weave is any combination of shafts which will give you plain weave. Not all weave structure are the same!
Overshot is a type of 'twill variation' (as one way to describe it) and generally plain weave results in tieing up shaft 1 and 3 on one treadle, shafts 2 and 4 on a second treadle.
Bronson Lace otoh, needs (again generally, it depends on how the warp has been threaded) shaft 1 on one treadle with all the rest on the second treadle.
Summer and Winter - again threaded differently from either of the above - is generally shafts 1 and 2 on one treadle and all the rest on the other treadle.