Common Suggestions and Feedback (with Dev Responses)

-Every Weapon type and basic Weapons have their own Blank version. So there would be a Blank Rusted Sword, Blank Driftwood Wand, etc. But only WEAPONS and SHIELDS.
-Every Blank Weapon cannot be Transmuted, Alchemized or tampered in any way. It also cannot spawn as Magical nor Rare item.
-It can exhibit interesting different effect(s) depending on what Gems are inserted into it, but as a catch you CANNOT retrieve the Gems directly from these Weapons. The only way to do so is to destroy the weapon (an NPC maybe?) and that would also confer a chance to destroy the Gems implanted inside, producing Shards (Idea number 2). Higher level gems and Higher quality Gems has a chance to be 'scratched', meaning they will either experience reduce in quality or turn into Shards (look at idea number 2 for this)
-Rarity-wise these would be somewhat rarer than Rare items, but not as rare as Unique. As rare as Skill Gems maybe?
-The number of slots are linked to the basic Item Level. But as a catch, all of those slots would be inherently connected for a different purpose than using a Support Gem. More details below.
-It will have a slightly different Slots distribution. Instead of the original distribution of:
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[]=[] for 6 slotted items, the shape of the slots will outline the shape of the weapon. So every weapon will have their own Link scheme. Swords would look like a cross, Hammers will look like a T, Bows like a C, and so on. This is purely cosmetic, though.
-The Slots will be divided into three categories: Active, Support and Effect Slots. Each Slot(s) can only be filled with certain Gems and inserting a gem into the respective Slots will confer special effect to the Skill, as well as giving it a chance to activate on hit (it should still consume Mana, though. Balancing issues and all).

*Active Skill slot: Can be filled with Attacking type of Skills. Includes Melee, Spell, Traps, Projectile, ETC. Gems slotted into this will gain different bonuses depending on the type of the Blank, 2 bonus being the Maximal number: one inherit bonus based on the category and one more depending on the type of the weapon.

#1-HSwords 2-HSwords, Daggers, Foils:
Increased Melee Skill Damage (All)
Reduced Skill Mana Cost (Daggers)
Increased Attack Speed (Swords)
Increased Attack Range (Foils)

#Maces, Axes, Hammers:
Increased Melee Skill Damage (All)
Higher Stun Chance and Stun Length (Club, Maces)
Increased Minimal Melee Damage (1H,2H-Axes)
Increased Knockback (1H, 2H-Hammers)

#Wands, Scepters, Rods:
Increased Magic Damage (all)
Increased Magic Critical Rate (Rods)
Reduced Cast Time (Scepters)

#Staff:
Increased Melee Skill Damage, Increased Attack Speed OR Reduced Mana Cost.

#Bows:
Increased Projectile Speed, Increased Critical Hit Chance OR Lowered Mana Cost.

#Shields:
Increased Chance to Guard, Increased Evade OR Increased Defense.

*Support Skill slots: Can be filled with Gems that conveys supportive effect, especially those which adds damage, adds special effect to attacks or such. Examples are HP Gain on Hit, Increased Flammibility, Added Critical Chance, Lesser/Greater Projectile or such. Aura Skill Gems can also be inserted into this Slot, for Example Anger, Wrath, Grace, ETC. Note that the Skills inserted in this slot would be ACTIVATED ON HIT, yours or enemies, including those which creates Mana Reserves. After brief period of nonaggression (not attacking/being attacked) the skill will dispell itself.

*Effect Skill Slots: Skills that does not contribute to final Damage output would be placed here. Examples are Item Rarity/Droprate and Skill Nodes such as Iron Grip or so. Notice that the bonus would only counted for 1/2 to 2/3 the normal amount. Again, balancing issues.

Now is the interesting part. Depending on what combination of Skill, Support and Effect Gems placed into a Blank, it would gain special effect: Either producing a Compound Skill, or getting a Title, or turning into a new category of Unique: Jeweled Unique.

For example of getting a skill, combining Skill Gems of Leap, Glacial Hammer and Frost Nova (in any combination) would create a Glacial Axis skill, which combines all three moves into one (Jumping high, smashing the ground below producing wide-range AoE Freeze damage), Fire Arrow and Poison Arrow will produce Acid Arrowhead, which deals Fire/Chaos damage on hit.

For example of getting a Title, combining a Life Leech and Mana Leech will bestow the title "Draining", which will also add "5% Damage Leeched Back as HP and MP" atop of the usual multiplier.

For example of evolving the Blank into a Jeweled Unique, putting together Skill Gems of Leap, Glacial Hammer and Frost Nova with Support Gems of Added Cold Damage and Weapon Elemental Damage would change a Blank Hammer (5 Slots) into Glacier Drift, a Jeweled Unique Hammer.

There's also the distribution of Slots, that is dependent on the weapon's type. It's usually following the 2:1:1 ratio of Active:Support:Effect, meaning for a weapon with 6 slots it could have 3 Active, 1-2 Support and 1-2 Effect slots, but there's always exception for certain weapons such as Staffs (2 or 4 Active, always 1 Effect, always 1 Support), or Shields (1:2:1). Again, balancing issues...