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Interiors International, Inc. I try to avoid green in bathrooms. The light reflection tend to make your skin look bad. You look like you have the flu.

Barbara Griffith Designs I would stay with the cocoa brown, and use the other colors in large pops of color..in towels, maybe choose ones with stripes or patterns, or mix & match colors. Also colorful much larger art.

rinqreation You could try and paint just the backs of the nooks and the rest of the bathroom the softest mellow yellow. Darkbrown behind the sink and toilet, a brighter yellow around the vanity (if there is any space besides the mirror?) Maybe then decide on wether to paint more of the nooks.
Like the comments above, accessorize with green and orange, when you get tired of them, no need for repainting the bathroom.

ASVInteriors I would definitely paint large swatches of any colour you plan to put in your niches. Artificial light can completely wash it out so you need to check this out first.
In your colour range, I would also avoid the green, I suspect your cocoa brown will wash out so I would go for the burnt orange - which is quite bold but, as a warm colour, will still hold fairly true and flattering under spotlights. Best of luck

Aegean-Designing Whims I'm also leaning towards the coco brown or the burnt orange. I've had both colors and loved them. I also would try some paint samples to see how the colors look once up. Chrysteen