this sounds like fun...
but it needs balancing (+4 skill ponts/lvl are too much)

and i have a question.
let us say i have a rogue lvl1.
and i take 2 ranks in weapon skill (katana) which is a non-class skill as katana is an exotic weapon. this costs me 4 skill points.

later i get levels with me rogue.
i get a bonus feat and i choose exotic weapon proficiency.
what happens to my already spent skill points?
"what happens if a feat promotes a (already trained) cross-class skill to class skill?"
i already have 4 skill points on the skill. the skill rank simply raises from 2 to 4? if yes, then what happens when my level is too low to have a skill rank that high? like i'm lvl2 with 3 ranks weapon skill (katana) and getting the exotic weapon proficiency feat, that would double to 6 but 5 is the maximum for my current level. the skill rank is lowered to 5 and i get a free skill point? the skill is temporaly limited to 5 and gets 6 automatically? or the skill remains at rank 3 and i lose my "cross wasted" skill points?

could we apply this to shield proficiency?
like an "opposed skill check" against the attacker to see if i can ADD the shield AC to normal (armor+natural) AC. how about that? maybe add the shields enchantments to the skill check.

or how about armor proficiencies?
like opposing rolls against arcane spell failure and EVASION checks.
like DC check against 10 + (chance of arcane spell failure/5%) or something.
like DC checks to see if you can ignore the dexterity penalty on your armor.