Apparently, Thunder-The-Bright already mentioned this but this is what I wanted to add!

The Proto Gear has the ability to upgrade through the process called Stratus Evolution. Instead of using the minerals themselves, the knights will experiment with the shards such as:
Red Shard
Blue Shard
Yellow Shard
Green Shard
Purple Shard

For a start on the one star level this could predetermine a specific attack damage.
My suggestions (for example):
x5 Red Shards
~Elemental: Fire Damage
x5 Green Shards
~Elemental: Shock Damage
x5 Purple Shards
~Shadow Damage
These are pure damage change, for multiple damage scales at this early state is based on the amount of a particular type of shards:
x2 Red Shards
x3 Purple Shards
~Normal Damage: Low
~Shadow Damage: Medium
I believe there should be a number of shards limit because knights tend to be power hungry at times to conquer other knights in missions or lockdown. However, as the weapon increases its star level it should be capable of strengthening its current abilities. Plus, at certain tiers they could only improve certain skills (except for attack damage, it should be able to get stronger like the Cold Iron Vanquisher or Archeron).

Tier 2: Focuses on abilities like charge time reduction, attack speed increase, etc.
Tier 3: Additional effects by the weapon(inflict burning, shock, curse, etc.)

Depending on what attack damage the weapon deals, it should predetermine what abilities and effects they are capable of.

Example: Dark Damage=Attack Speed Increase=Curse
Based on this method, the basic normal cannot be handicapped. In order to prevent this, the weapon has the ability attain additional effects by luck or gain any second ability other than the ability it already has.