How about one of the King snakes? They are easy to care for and have a great feeding response. The florida kings are really nice looking, and so are the easterns. There are also the tri-color kings from out west. And the california king comes in a variety of morphs as well as the natural occurring desert and coastal phase!
I have a california king that was 48" a couple of months ago when I measured him. He is the coastal phase. The desert phase is white and black banded.

I also have a hatchling black king...

And a prairie king...

Then there are the various rat snakes. They get pretty good sized and are for the most part mellow tempered. The black rat comes in lots of different morphs and are the largest of the rat snakes. The record black rat snake was 101".
Here is my Kentucky locale black rat snake. They dont get jet black like the black rats on the eastern board and the south. The last time I measured him he was 54" and he is 2.5 years old!

Here is an albino, he is Dwight Good stock and has retained alot of orange. He is about 1.5 years old. I havent measured him lately.

I also have an everglades rat....

He should turn all orange as an adult. But they are pretty variable as well.
And a yellow rat snake....

She should turn a shade of yellow with a pair of stripes down her back. They are pretty variable as well and can be a light yellow to a dark yellow.
Hope you enjoyed the pics.
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1.0 Corn snake
1.0 Black rat snake
1.0 Albino Black rat snake
1.0 Everglades rat snake
0.1 Yellow rat snake
1.1 California king snake
1.0 Prairie king snake
0.1 Black king snake
Good luck and Happy Herping
Brian