Currently you can turn on up to 3 LDR modules, which makes your choice pretty inflexible and stable.
I was thinking about ability to turn on any amount of modules, limiting its effectiveness.
Effectiveness of each module could be represented by some value X.
X always less than 33.(3)%. n - amount of turned on modules.
If you turn on >3 modules, effectiveness will become 100 / n.
So 25% for 4, 20% for 5, etc.
E.g. for Damage Resistance current max output 15.
100% effectiveness 15 / 0.(3) ~ 45.05
If you turn on 4th module, its output will be 11
If you turn on 5th module, its output will be 9
(I'm partially using indirect calculation for the max output, I think there is better way to calculate it without knowing "max potential output").
This change will be pretty gentle. Nobody has to use >3 modules, as 3 modules are staying the most specialized way to share bonuses. But it provides more flexibility/versatility for cost of effectiveness.