It order to make sure everything is proportional when it comes to making shorter sims, the following sliders are what I use.
[All of the below links are direct download links taken from the creators themselves. SO, no worries, I have not re-uploaded them, just skipped a step for you guys. However if they don’t work, clicking the creators name will take you to the original post.]
Leg Length, Torso Height, & Arm Length Sliders by Johna
Feet Size Slider by NikSim [Requires Registration]
Some of these sliders (Such as both slider downloads by Johna) will come with other body sliders, however the ones I have listed are the only ones you need if you want to make your short sims proportional.
I hope this has been helpful! Happy shorty making!