Sofa Upholstery - What colour?

Dark charcoal grey or black with nailhead trim?

I have two rather sad sofas sitting at my house at the moment; both are waiting for a makeover. Apart from the lack of time, they haven't been re-finished because I'm being rather indecisive about the colours! 

One is a contemporary high armed sofa, with no back cushions and is currently navy. It was supposed to be going upstairs in the living room (hence the navy, black, grey and mustard colour scheme). But...

I bought another small sofa as well. It's slope armed with a smaller foot print and currently some kind of hideous diagonally striped, grandad's wooly cardigan style fabric. It will fit much better upstairs.

The result is that both now need upholstering and I have to choose the colours...

Light grey-brown?

White? (That's already a no - not with dogs inside!)

Black?

I like this dark greige colour on the armchair.

Light grey with contrast piping.

Black with white piping.

Beige - like this but maybe too light?

Oh, I would love stripes.

All photo sources can be found at my Pinterest page.

I think I'm leaning toward charcoal or navy upstairs (with mustard yellow and maybe some coral accents), and a browny-grey-greige colour for downstairs (with some orange accents).

Does anybody have any suggestions?