For a brief time, I was slightly against the current artemis stats, but honestly the end result is that I agree with the OP, but in a different way than he intends. Art meta is boring, but I find it that way because you have 3 of the same gun, and your counter is going to be the same. You don't get any better, and it honestly isn't that challenging to go up against. Pop a balloon and get directly above the artemis ship and you can 2v1 pretty effectively.
Realistically, 3 of the same gun will never be as effective as a mix of guns. I fear double artemis-hades significantly more. You suddenly get upwards arcs, armor piercing, balloon damage, fire, etc.
I don't think artemis are overpowered. Overused? Certainly. But stick a bunch of artemi together and its sorta boring and easy to counter. You are only ever thinking up strategies to counter one build.
Now mine launcher-carronade on either side of a junker. That is terrifying.