The whole concept of not wearing black and brown only really applies to formal looks; what you were wearing sounds pretty awesome. As for other pieces of footwear I think any type of black shoe is a safe bet (your idea of Chelsea Boots sounds good) or a simple pair of black/white/coloured trainers. If you're feeling very brave then perhaps sling on tan belt/brogues. It would be a very strong look but if you can pull it off then you'd look awesome!
Hope this helped