Canis Major the Greater Dog is most famous for being home to the brightest star in the sky, Sirius. You can see it in January following Orion from the horizon.
Why search for such a faint constellation? Only because it's beautiful. Plus seeing Eridanus can give you a kinship with stargazers from centuries ago.
Orion the Hunter may be the most recognizable constellation, visible from both hemispheres. It's best in winter from the north and summer from the south.
Fornax the Furnace appears as a few dim stars to the unaided eye but harbors galaxies from one orbiting the Milky Way to some at the edge of the universe.
Cetus the Whale is a huge constellation that swims in a sea of stars near constellations named for a river and fish. It contains a wonderful variable star.