Thanks for the correction!
In card design, power seems to be more expensive than hit points.
Here we are...Thanks to you for this topic ;-)
I guess yes, that's a ratio they're considering in design.
The general pattern I'm seeng from Hastur's spoiler is: power equals to half resource cost (round down). Hit points are usually 1 to 1 ratio barring useful ability and/or high powers that may knock it down a notch.
Because the Kingdom zone produces a base of 3 resources every turn, the basic lower tier units seem to look like this:
1 resources, 1 loyalty, 1 power, 1 hit points.
2 resources, 1 loyalty, 1 power, 2 hit points.
3 resources, 1 loyalty, 1 power, 3 hit points.
4 resources, 2 loyalty, 2 power, 4 hit points.
Higher tier units and heroes have more variable hit points and power. Faction defining units and cards with powerful abilities are also heavy loyalty cost as expected. Self-granting low power Keyworded (toughness 1, counterstrike 1, scout) units does not seem to break this formula until other factors weigh in to give it more oomph.
Heroes also seem to follow that pattern except they have higher loyalty cost (usually equalling their resource cost) and the severe restriction of hero placement (unique and 1 per zone). Dwarven Durgnar with -1 hit point and +1 power, the dying high powered Thyrus, and mobile but low powered Johannes are slightly oddball but well within accepable limits. Chaos heroes have lower loyalty cost than other heroes due to limitation of their ablities being dependent on corruption.