Isn't there more to being an alpha female than just being loud and obnoxious? She has no power in the house at all, she's not a strong woman, most of her ideas are stolen from Linda, she appears to have few opinions of her own. She needs to have people on her side. That's not alpha!
Liz was way more alpha, she did her own thing, had her own opinions and didn't give two shits if people understood her or liked her. Luisa is a people pleaser, every thing she does is for attention, she'll irritate someone just to get their attention. Liz told that big brute she's stab him if he punched her horse. Now that's alpha! Luisa would have giggled or said something silly to him in her baby girl voice.