from my experience playing the game what you've proposed is a valid next step as the skills, and therefore the combat, has never been the greatest.
personally the stat I would always put everything into was the charisma one as it effected what I believed to be the main premise of the game: dialogue and character interaction. so it would be nice if it stayed in one form or another.
personally I believe the combat system could use some tweaks on top of the skills rework. like the amulet giving you an extra stamina compared to a card that gives only one.
but I'm getting off topic a bit, from what I read with your rework idea you're moving away from three general skills/stats to multiple skills that increase there own thing. while reading both your and other's ideas I've decided to give my idea.
Skill #1: this should be something that boosts your sword attack by 3-5% per level and at max maybe it will decrease the stam cost of attacking by 25-50%
Skill #2: this needs to be a way to help us take hits, you could increase the players health by 2-6% per level and give the player an extra 1-3 stam at max or give an extra 2-4% block power and at max decrease the stam cost of blocking by 25-50%
Skill #3: would most likely be much like the charisma stat is now in giving us new diolauge options, lower item prices and maybe at max allow us to get a higher selling price.
Skill #4: would increase item drop chance by 5-10% and at max give us a % chance to gain an extra item.
Skill #5: increasing crit chance by 1-5% per level and adding a %chance to gain a bonus attack at max maybe?
the player could chose how to invest in those five at the start an then you could make it so that the player has to seek out the other skills they want from learning them from other characters, these characters requiring you to do some quest to gain the requirement to unlock them.