Mike
I would say you cant go wrong with a yellow rat. The care is pretty much identical to the corn and cali king you have now. The yellow will get bigger than the corn and king, and the temperament should be easy going.
As far as "taking a step forward or backward" when it comes to owning a snake, I wouldnt really put it in those terms. A yellow rat would be no problem for someone that has the experience you have, and would be fun. The ease of care and easy attitude is what attracts me to the NA rats, and not to mention the multitude of ssp mother nature has provided!!!!
So I would say yep, go ahead and get the yellow if that is what you like! They are a beautiful snake, but be careful, you may end up with a few other Obsoleta sub-species once you get the yellow!! LOL That is where it always begins!!
Have fun with the hobby, and if you decide to get a yellow, post some pics.
Hope you enjoy my post above, my yellow and everglades.
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1.0 Corn snake (KY locale)
1.0 Black rat snake (KY locale)
1.0 Albino Black rat snake (Dwight Good stock)
1.0 Everglades rat snake (Dwight Good stock)
0.1 Yellow rat snake (Dwight Good stock)
1.1 California king snake (Coastal phase)
1.0 Prairie king snake (KY locale)
0.1 Black king snake (KY locale)
Good luck and Happy Herping
Brian