If something is seemlier, it looks better or more suitable in a certain situation.
Seemlier is a good thing. It means something looks right or better than something else.
Examples:
The seemlier dress is the blue one.
The seemlier place for the flower is in the sun.
The seemlier choice is to go to the park.
The seemlier cat is the one with the fluffy tail.
The seemlier way to go is to walk on the path.
The seemlier house is the one with the big garden.