...any teen/preteen character should be more “generic”, (like Murgatroyd’s Tweens) allowing the artist to create the individual “personality” through use of morph controls and/or combining aspects of other “characters”. This is the whole beauty of the Genesis figure.
To create the latest version of Leela, I used:
Steph4 (via GenX - primarily for the extra body morphs and NPMs)
Genesis Basic Child
In some cases seemingly “contradictory” morphs (like Basic Child and Steph 4 “Lanky”) were used to adjust proportions as the Child shape also affects torso and hip volume/scaling while “Lanky” adds that bit of “ungainly” stature many pre/young teens have.
Yes it is a lot of effort that will of course become moot once Thorne’s Teens or Daz’s L/L5 are finally released, but until then, as others have said, this is all we have to work with for now.