I don't know that EVERY album really had 1 more single that could/should have been released. but certainly there are some

now you can't change what was released. so the A and B sides that were already out from the album are off limits lol. But what should have been 1 more A side?

Love child - evening train
new Ways - Together we can make
Jimmy Webb - 530 plane
Touch me in the morning - all of my life, then a 3rd single we need you
last time - stone liberty
the boss - once in the morning
mary scherrie & susaye - don't want to be tied down
everyday is a new day - Carry On