Basically, I'm looking for a Default Replacement Skin Texture with good cleavage? Please don't report me, it's just the only way to say it. I'm having a hard time finding one and I'd like it to work for all ages and genders, because it's kind of weird to have my female sims looking great from YA+, but then anything male or younger females looks like .
Thanks so much!

Try looking here: https://sunnyccfinds.tumblr.com/tagged/skins
and
http://sssvitlans.tumblr.com/tagged/s3skin%20default

Have you checked out Lady Frontbum's skins? Either her Busty St. Clair skin or Naughty&Nice skin? There's a Naughty&Nice skin seperately available for males, as well.
http://www.ladyfrontbum.com/?category_name=genetics

http://kurasoberina.tumblr.com/post...y-elder-this-is
I think skin won't do any difference if your teen female sim has small breasts. I use sliders to enhance their bodies as sims grow older.