Also try thinner higights vs chunky.

I would also do balayage or perhaps change the tone of your highlights. They're washing you out bc they're too light. Try a warmer blond or lighter brunette.

Do a glaze on your natural color.

I get dark brown with caramel highlights.

I would look into a subtle balayage.

OP here - thanks!

Get some warm brown highlights

I am naturally brunette. Over the past few years I have been dying my hair to color grays. I started by doing an all over color to match my natural color. The past year or so I have added blonde highlights. I have decided that blonde makes me too washed out and I need to go back to brown. The problem is I feel that all over color is one dimensional. Is there anything I can do to have brown hair without it looking dull or drab? what coloring techniques should I ask for? Thank you!