One example: Each time you create unnecessary array objects with this code in setAnimUV()
.
anim.meshGroup.children[spriteIndex].geometry.faceVertexUvs[0] = [];
// TL , BL , TR
anim.meshGroup.children[spriteIndex].geometry.faceVertexUvs[0].push([
anim.UVList[spriteIndex][0],
anim.UVList[spriteIndex][2],
anim.UVList[spriteIndex][1]
]);
Try to avoid this. Instead, reuse the arrays and just change their content. Your app will allocate less memory and the garbage collection has less work to do.