Currently there is a large discrepancy between light and heavy armor.
Currently heavy armor is for characters with low dexterity. Generally, this means characters with high strength (Although not necessarily). I think a large part of the gap between armor can be addressed by making heavy armor designed for high strength (As it is implicitly with its higher bulk). This is achieved in that any armor with a strength cap adds up to that much strength mod to ac.
The idea is to standardize armor generation into 3 'tiers' per weight class.
Light0 (e.g. Unarmored) gives 0ac, 0tac, and has a dex cap of 7. It has no drawbacks
Light1 (e.g. Padded Armor) gives 1 ac, 1tac and has a dex cap of 6, it has 1 drawback
Light2 (e.g. Leather) gives 2ac, 2tac has a dex cap of 5 and has 2 drawbacks
Medium0 (e.g. Hide) gives 0ac, 0tac, has a dex cap of 4 and a strength cap of 3. It has 1 drawback
Medium1 (e.g. Scale) gives 1ac, 1tac, has a dex cap of 3, a strength cap of 3. It has 2 drawbacks
Medium2 (e.g. Breastplate) give 2ac, 2tac, has a dex cap of 2, a strength cap of 3. It has 3 drawbacks.
Heavy0 (e.g. Splint Mail) gives 0ac, 0tac and has a strength cap of 7. It has no drawbacks
Heavy1 (e.g. Half Plate) gives 1ac, 1tac and has a strength cap of 6. It has 1 drawback
Heavy2 (e.g. Full Plate) gives 2ac, 2tac, and has a strength cap of 5. It has 2 drawbacks
Armor individualization can be best achieved by choice of drawbacks.
Medium armor has an additional drawback because its innately easier to get a higher combined dex+str score then it is to get a high str or dex score.
This removes most of the raw power difference between armors, while still allowing for the expression of different unique armors.
For example, both leather and studded leather could be Light2 armor. Leather could have a check penalty and fragile. Studded Leather could have a check penalty and increased bulk.