I like the living weapons idea. Reminds me of that living armor in one of the Spelljammer 2e Monstrous Compendium (bionoid?) and Eberron's Daelkyr grafts.

So far you've only focused on offense and defense. Are you going to have any non-lethal versions? Here are some ideas:

Weapon types:
Silk Spinners
Silk-producing organs on the forearms allow the wearer to spray webs as Web spell by 5th-level caster.

Paralytic Parasite
Appears as a Spike Lobber, but fires a burrowing parasite that latches onto the target's nervous system. Acts as Paralyze spell.

Living Armor Types:
Scout Suit
Enhanced arm and leg muscles boost the wearer's movement speed (maybe by granting Run or Sprint feat or just a flat bonus to Move?)
Leaping ability (bonus to Jump and Slow Fall as monk)
Hands and feet can produce gripping hooks and secretions at will, activation 1 round, acts as Spider Climb spell

Glider Suit
Bladders along the arms, legs, and back can inflate with the metabolic waste gases of the suit at will, taking 3 rounds to fill. Acts as Levitation spell (or Feather Fall).
Folding wing membranes along the arms and legs give the wearer a glide speed of 30'.

Sensors
Symbiotic sensory stalks graft to living armor and the wearer's nervous system allowing a wider range of senses:
Eyespots - Rudimentary chitinous eye buds are dotted all over the armor allowing the wearer to see in all directions (acts as Robe of Eyes)
Psisense - A psionically-sensitive organ allows the wearer to use Detect Psionics as per the psionic discipline
Tactile Nerve Endings - Movement-sensitive nerves infuse the suit giving the wearer Tremorsense
Heat Pits - Heat-sensitive pits in the suit give the wearer Darkvision to 60'