I'm not living in the US but i think it would be a good idea. The most obvious, biggest benefit is the very different directions that people in the US want to take. It's just very clear that the lifestyle differences between rural and urban US are practically irreconciliable. You can't have one country when people want to tear it apart.

I think financially, it wouldn't really make a lot of differences. The people would have to pay their taxes directly to the state, instead of the federal government, which is a manageable step. I think the blue states might draw a tiny financial advantage from it, while the rural areas would possibly suffer a medium-sized disadvantage, because today, most blue states pay more in taxes than they receive back, and vice-versa for rural areas. But i suspect the issue might balance itself out over time with internal reforms in the rural areas.