If you're going to get into building girl packs, a few tips...
1) Most non-sex tags work OK with multiple characters in them in non-sexual positions. For example, "Rest" would be fine with two girls (including the focus girl) sleeping on a bed.
2) For Profile and Portrait, OTOH, try to stick to single girl pics of the focus girl. These pics get used to illustrate who the girl is. Multiple characters in a Profile pic can be confusing for which one is the focus girl. Don't assume that everyone who uses your pack knows exactly who the girls are. This can be especially confusing when the pics get used to represent the free girls hanging around town.
3) Also for profile pics, try to avoid pics that are wider than they are tall. For free girls, if you end up with more than one of these in the same zone they start to encroach on the buttons on the page.
4) If you are having trouble finding good pics for Portrait, make some yourself. Cropping down images is super easy in most editing programs, so select any other pic with a good view of her face and crop away.
5) Be very, very careful with the Naked tag. This can be one of the most immersion breaking tags when misused. The girl is not supposed to be seen naked until/unless the situation warrants it. If she is showing tits, pussy, or asshole, and it is not a sex act, farm, or fixation/hangup pic, then it really should have the Naked tag.
6) If you are unsure of the proper use of a tag, check the tooltips. Goldo has put effort into trying to have those tooltips clear up any confusing spots in the use of certain tags.