I've given this thought, & I'm not sure that capital punishment is something that should be necessarily ruled out for regions to use in extreme cases.
Why should it be any different than for the federal government?
I would prefer generally decentralized power. Regions have the freedom to eliminate the death penalty themselves, but I don't see the great need to force it on a region that does not wish to forgo the option of using the death penalty.
I agree with this. I do not have any inherent opposition to the death penalty on ethical or moral grounds, but rather for financial reasons. Assuming a region is willing to undertake the financial burden of capital punishment, I do not believe the federal government should be able to compel them to remove the death penalty.