Unit cost advice - Mod related

[Wauthan]

Being the kind of person that I am, I keep tinkering with new mod projects. Since the Last patch things are looking brighter and I might actually come up with a useful idea.

I still have trouble calculating gold and resource cost for new units. Sure I can just tweak the stats to fit my own playstyle but experience have shown me that this might not be a good idea at all. I've tried to come up with a basic formula for the different equipment and combat prowess. Frustration did however get the upper hand since logic will always be a lot less helpful than common sense.

So how do you fellers decide how much a unit oughto cost in gold and resources? Not in the big chunky way but in the fine details. Does a Lance always cost 20 resources, a broadsword 3 and a leathal Baneblade a mere 1? Does 16 morale warrant a 20 gp goldcost on a feeble militia? How much more if it's sacred? A heavy infantery cost 10 gp and 20 resources for a 15 prot medium unit. How much more would it cost in Full Plate Mail? Does a 15 prot Troll without equipment gost 20 resources as well or just 1 and extra gold?

What does goldcost and resourcegost actually reflect? My own guess have been that gold reflects the "worthiness" of a unit. A Troll is a lot more expensive than a heavy infantery because its a big badass monster, and well aware of it, and need a lot of gold just to keep under control. How much then are the values on the different abilites in your opinion?

Resourcegost seems to reflect "construction time". A leather cuirass is apparently churned out pretty fast while a plate cuirass takes a while. A shortsword apparently takes just as long to create as a broadsword. A battleready Sea Troll seems to be really easy to find, though expensive to hire, while recruting an ordinary Troll takes twenty times longer. I understand that the function of resources is to place an upper limit to the recruitable number of units (given high amount of gold). But how to you value resources in the fine detail so that one unit cost 3 more than the other though they both have the same equipment?