It would have some appeal for a state like Texas, or Florida or any coastal state with resources or tourism. North Dakota, flush with energy $$, while landlocked, might find it appealing.
The hard part would be unbundling all the federal infrastructure investments and figuring out what would have to be paid to Washington D.C. as an exit fee. Probably not worth the exercise.
Rather than secession I would think that there could be some rationalizing of state boundaries, and consolidation of several Northeastern states. The UP of Michigan belongs with Wisconsin, probably the panhandle of FL should be southern Alabama.
But that too is a pointless thought experiment, since political boundaries, however drawn, become entrenched. Atlanta, the city of and the metro area of are perfect examples. There should be a metro area government, essentially a super county, made up of 8-10 of the counties in the present metro area. But the City of Atlanta would never cede power. Never going to happen.
10 or 12 years ago Staten Island seriously investigated seceding from NYC and assuming status as a self governing county per NYState constitution. The pros were release from Manhattan centered city govt, lower taxes, control over local schools etc. However the cost of reimbursing the city for facilities, roads, traffic systems, fire equipment and stations,hospitals, school buildings, water and sewer systems, continued connection to the city’s water supply and a host of other issues would cost so much that Islanders would see no positive financial benefit for 50 years. The issues of secession from the US would make the case of Staten Island seem like an adult child deciding to go out on his own.