ok so here my 2 cents about the matter:

Increasing the cap aka maximum lvl of any feature that requires you to lvl up on each position individually actually reduces the amount of teams that are viable.

The reason for this is that now with a lot of people reaching the point of refines, charms and runestones beeing maxed on not only their position 1 but also on position 2 and working on their positions 3 and 4, we can see a lot of teams actually gettin viable that require 2 or 3 ninjas to work.
Our game always had the problem of beeing accelerated far too fast, which made a lot of ninjas and teams absolutely horrible because they werent selfsustaining and needed support. This problem is slowly but surely finally fixing itself with the release of the ninja assist system but also with the fact that people are reaching the maximum lvl on the older power systems that needed you to lvl indiviually for each position.

In other words, increasing the level of runestones, refines and or charms would be a giant leap backwards and would actually take out air of the game instead of bringing new air to the game.