Striker is all about being offensive. And in order to be able to play offensive you need to balance offensive,defensive and sustain.
1point of stamina = 30hp
6piece classified striker gives a base of 0.01% health/second as regen.
Then an additional 0.05% health/second for every 3000 stamina you have.
And since regen is based on your total, and the stamina itself also boost your base health the actual health/second increase is alot more then it would seem.
1-2999 Stam you will heal 0.01% of your total health pr second for each stack (100stacks 1% healing pr second).
3000-5999 Stam you will heal 0.06% of your total health pr second for each stack (100stacks 6% healing pr second).
6000-8999 Stam you will heal 0.11% of your total health pr second for each stack (100stacks 11% healing pr second).
9000 Stam you will heal 0.16% of your total health pr second for each stack (100stacks 16% healing pr second).
9k striker should have roughly 420k total health, so 67k heal/second with 100stacks.
6k striker will then have 90k less hp(3000 stamina x30) = about total 330k health, so 36k heal/second with 100stacks.
As reference the reclaimer support station gives about 33k heal/second with 10k electronics.
So to sum things up 9k striker provide almost double the healing, while doing about 30% less damage.
But calculated damage does not mean practical damage. In reality the additional healing and max HP allows you to:
Never needing to hide in cover, so you always have a target to shoot at (more damage over time and faster stacks).
You can move closer to the targets, easier to land hits and force enemies out of cover (more damage over time).
Being closer, you can land headshots more consistantly (more damage over time).
Never outside optimal range(more damage over time)
At the end of the day, in most situations, you will end up doing alot more damage over time.