This is a true slider lora so it should not change the image to much compared to normal loras. Its also no problem combining this lora with other loras.
The lora is very weak, so if the prompt specify "high-waist" etc, the prompt will probably override most of the lora-effect.

I RECOMMEND COMBINING medium and strong for best results.
Strong have a tendency to unbutton or rip the pants. But with medium at around 4.0-5.0 combined with strong at around 1.0-1.5 its perfect imo
medium is has better quality, but strong works where medium is limited.

Recommended range
medium: -5 to 2 (negative = lower)
strong: -4 to 4 (negative = lower)