It's very, very, very unlikely for any two states to merge.
Between them, the states would have four senators, two governors, two lieutenant governors, two speakers of state houses, two speakers of state senates, dozens of statewide elected officials(AGs, secs. of state, insurance commisioners, etc.), state supreme court justices, dozens of agency heads, many dozens of agency sub-heads, two of each single position state employees (How many people regulate health codes for the cosmetic permanent makeup industry? I'm guessing one person in each state.), heads and officers of unions that represent state employees and teachers, and all the ancillary personnell thereof, from the secretaries in the Governors' offcies to the people who make the meals in the state capitols' cafeterias.
That's a whole lot of people facing possible redundancy. And a whole lot of very powerful people who will oppose combining any two states, no matter how laughably low of a population or land area they have.