Well, I'm sure this isn't the answer you are looking for, but I'll have to say "mixed media!" That's because I can't choose just one! I often work in watercolor, acrylic,
gouache, gold leaf, pigmented wheat paste and collage papers all or some at the same time. Each one has its strengths which you already know--watercolor for briliant
transparency, acrylic for waterproof properties, paste for texture, etc.
How's that for a NON-answer!
Carol