Doing Stuff in Age of Man (Feedback wanted!)

Right now my homebrew system, Age of Man, is messy. But I hope to make tasty gumbo out of it someday. Here are the mechanics that exist so far:

The Primes

When making a character, roll or point buy your four prime attribute scores. These determine your character's aptitudes and basic abilities.
Body - How well you can bash skulls, take a knee to the groin, wrestle livestock and carry your spouse across a swamp. Determines hit points and melee prowess.
Agility - How well you can dodge bullets, catch falling children, juggle knives and pull off sick stunts on horseback. Determines defense and ranged weapon prowess.
Mind - How well you can decode encrypted messages, memorize dungeon layouts, apply physics to take out a room full of goblins and beat Gollum in a riddle contest. Determines number of proficiencies/areas of knowledge/languages.
Soul - How well you can keep cool when the walls are closing in, ward off angry spirits, deflect a witch's hex and seduce the chaste elf priestess. Determines will power and spell resistance.

He got a high roll in Smug.

The Derived

Six attributes are derived from combinations the four primes. These are used when determining most resolutions. If you aren't making a straight-up attack, you're probably rolling for one of these. You gain bonuses to these attributes depending on your character's class.
Grit - Enduring unpleasant situations. Can you run with a musket ball in your torso without keeling over in agony? Body + Soul/2.
Insight - Making quick, accurate observations. Is the highwayman holding a dagger to the girl's throat bluffing? Mind + Soul/2

Poise

Poise - How cool you are when things get hot. Can you talk the enraged giant out of going Godzilla on the village? Mind + Body/2
Deftness - Ability to act with swiftness and precision. Can you attach the grappling hook to the balcony before the swarm of spiders overtakes you? Body+Agility/2
Expertise - Completing tasks that require focus and skill. Can you mix an anti-venom before your friend puffs up like a toad? Mind + Agility/2
Reflex - Effectively reacting to danger or opportunity. Can you dodge the pendulum blade that's flying at your face? Agility + Soul/2



There are two types of resolutions. Attacks use the standard d20 + Fighting Ability + Body or Agility mod. These rolls are strictly hit or miss.

Other rolls use a system similar to Dungeon World's: 2d6 + derived stats. Rolling 10 or above gives you a clear success. 7-9 is a success with a hitch. For example, you're jumping off of a bridge and landing on a wagon full of hay. The DM tells you to make a reflex roll. On a 10, you land in that hay with the grace of a ninja cat. On an 8, you still land in that hay, but you twist your ankle and you're slower for the rest of the day. On a 6, you'd miss the wagon and land in a heap of road apples or something, taking some hit points along with that twisted ankle.

I'm kind of stepping out on a limb with these rules because I've never played a game that uses derived attributes, and I haven't tested Dungeon World's resolution system very much. Give me all of your feedback, or I'll cut you good. Stay tuned for character classes tomorrow or the day after!