My group has yet to make a brown/tan steampunk. We always choose a base colour, usually a jewel tone, and go from there.
But I do admit I myself am partial to grey velvets and brocades, I often pair them with bugundy or navy blue accents. It's what I look good in and I have the "If I were in Victorain England as myself, what would I want to wear" And I go flipping through my clothing catalogs and pick a dress style and shove some steamy bling on it once it's made. ^^;
My sister loves more pink tones like bright raspberry and light sky blues paired with greys to match her eyes. She's yet to try tea dying, all her blouses and ruffles are actually white and give a very futuristic/clean pressed military look when paired with all the buttons and gears and things.
Men I can see being more drab in their colour choices unless they're doing an aristocrat/dandy sort of character. But a little splash of colour here or there never hurt anyone, especially in lining colours, cravats and hat bands. Just pick one colour and have hints of it throughout to get a unified look.