I had this thought, recently (as in yesterday), on modifying skills similar to my thoughts on a 'Magic Skill' to diversify casters more.
Basically, it breaks up some of the more powerful or frequently used skills in a similar fashion. For example, Perception could be further customized by granting 3 sub-ranks for every rank in perception. Then you could use those sub-ranks to specify what type of senses you've practiced, those senses being Smell, Sound, Touch, Taste and Vision.
So someone with 5 ranks in Perception could be further clarified to have the following:
Then you would adjudicate the various perception checks based off what kind of check it is. So, for example, instead of just using Perception to identify potions, you would instead use Smell, or Taste to do so. It's also easier to make a blind character this way, as one could dictate a blind character being incapable of adding points to Vision.
It also doesn't take away points from normal skills, it just makes people specify what 'type' of perception the character is good at.
I've had a similar thought for an 'Agility' skill, which would cover Balance, Acrobatics, and Jump, but in addition, every 5 ranks in Agility would grant a +1 to Reflex saves. So a Fighter who practices in Agility maneuvers would actually have a fairly decent Reflex save as a bonus instead of the crappy they save they have now, even if they are good at Balance and Acrobatics.
Do you think a 'sub-skill' type of system might make a Skill system a better system over-all? Would you find it more realistic? What are your thoughts on this type of system?
While I think the idea of a magic skill works pretty well, I'd be concerned as to the complexity of having multiple subskills devoted to other skills. Mostly because it would add a lot more bookkeeping to deal with and make it all the harder to introduce to new players.
It's a constant war between better emulation and manageable gameplay. (o_o);
I shudder to think what writing a statblock out would look like. :P
That said, we will certainly have multiple sub-uses for skills, so without going into the extra bookkeeping of having different ranks and such in in subskills, it would probably be pretty easy to categorize what sort of senses fell under perception and make notes such as "Scent gives a +10 circumstance bonus to Perception checks based on sense of smell" and stuff like that, or allow for tradeoff or specialization mechanics if you wanted to include those sorts of things.
You'll probably see a lot of this sort of thing in Athletics (our catch all for climb, jumping, swimming), Acrobatics (balance, tumble, fly), Perception (hearing, vision, olfactory), and stuff like that.