Hi, I feel like I am posting this everywhere, but maybe you want to try Yes To Carrots Leave-in Conditioner. Obviously it's not for everyone, but you can browse the website a bit and find out more. I find the leave-in very moisturizing for my 2b hair. It also has protein, I think.
I just use it because it feels very moisturizing. It's a nice creamy texture, doesn't have much hold and doesn't fight frizz too much. It mainly conditions and softens my hair. Other than that, I would try a moisturizing butter. Even if you just get a sample of a hair butter, you can try it once or twice and see if you feel a difference.
To fight frizz I just run some gel through my hair when it is dry. Since I don't have much hair I like the volume that I get from using minimal product.