IMO the loss of peripheral vision and cold blooded make it balanced. Maybe not 100% balanced, but I don't think it's quite as OP as people say it is either.
I usually only use it with the FAL (where it truly shines), and usually only on maps like Carrier or Turbine. Plus, with semi-autos its important to land as many hits as possible so it's very useful in that regard.
They don't need to do a lot. They should just lower the recenter speed or something. TF just makes a bunch of the sights seems pointless on long range guns
This isn't coming from a place of hate btw. I occasionally use target finder on my mk I just think it makes other sights a waste since there's ALMOST no downside to TF.
I don't like target finder 'cuz it encourages camping. It's like auto-aim assist (as if auto-aim wasn't enough). Making the field of view smaller would be my nerf of choice. Target finders would still be able to camp choke points and not capture objectives or move. They would just be slightly more vulnerable.