Just a quick little blurb here about a couple of house rules I use in pretty much everything I run (mostly).
The first is regarding the 2 points of DR that the skull offers. I don’t actually treat it as regular DR, it’s just there to prevent the first two points of damage from being quadrupled for being a brain hit. So if a character gets stabbed in the skull for one point of damage, they still take one point of damage, the “DR” just prevents it from being a brain hit. I do the same thing for the torso in regards to vitals damage and impaling type attacks. The ribs are supposed to protect your vitals (at least in the upper torso) and this rule lets them do that without actually stopping the attacks (which would be kinda silly).
The second house rule is more far-reaching in that it affects the mechanics for magic in most of my campaigns. In both Domibia and the dimension hopping campaign I use a pool of magic points, rather than FP. All characters have magical energy points equal to their Will squared and then divided by (10- Magery) that are free of charge. So the average person, with no magery, has a Will of 10 and thus Magic Energy of 10^2/10 = 10. A Domibian wizard might have a Will of 14 and Magery 3 giving him 28 Magic Energy (14^2 = 196/7 = 28). I usually treat Will and Perception as separate attributes, divorced from IQ. Characters can still try and use FP if they need to, but since I also use the expanded Fatigue rules from The Last Gasp, that can be a slippery slope.
I think this second rule is a result of my formative gaming years being spent playing Runequest where you use Willpower to fuel spells. I haven’t noticed any balance problems with either rule. They both cut both ways, so they seem balanced…