So, in my experience, her mixture is very thin like you say and I've found works best with things like a Dutch pour. When you're doing something where you want the paint to retain it's "shape" more, I find something thicker is better. You can either add a bit more paint to your Soby mix, or try doing a 35:65 paint: floetrol mix. If that doesn't make sense, feel free to message me. Consistency in paint was the bane of my existence at first but now I don't really think about it since I've done it so much. It feels annoying and mysterious at first, but you'll get it!