Perhaps it's furry encounter which is causing this, last time I played (roughly 3 days ago) they are working as normal and I am seeing various different slime types.
In all the versions of the game that I play, I turn the furry levels to maximum. I do disable some races (don't need 20 dogs and birds), but most of the races are enabled and the human spawn rates are only 5 or 10 percent.
Are you loading a save that you used on a previous version of the game and then just looking at the slimes already spawned in your game?
The issue seems to be with new, random, spawns in the game, not with slimes that are already spawned in your save file from previous versions.
I still have a copy of 0.4.8.9 and the very first slime I spawned with the buggy command, in that version, was a catgirl slime.
In 0.4.9 I fiddled around with settings, deleted my properties.xml file, loaded a pair of different saves and using the buggy command, spawned in 4 or 5 greater slimes and they were all humans.
It doesn't matter to me much, whether it is a bug introduced by Inno or something in my game, I don't play around with slimes very often, was just trying to help the other person figure out if the problem was their install or not.