But you say you want to make things more interesting... How about turquoise shoes? Turquoise goes very well with those types of wine/plum/aubergine/maroon colors.
Edit: I wear turquoise/aqua with my maroon together all the time, especially in the fall.
Example from last September. This was a game day outfit for me.
Probably not practical at all, but so cute! I'd buy other clothes to be able to wear the shoes. But I own quite a few pairs that only go with a couple of things, so I'm probably not the best to ask.