The red & black halved shirt is definitely the best one in my living memory.
I wouldn't be averse to having different colour options, but the halves are our trademark and should be used for both home & away.
Other than the red & black mentioned previously, the yellow and black (similar to Watford's this season but halved on the back as well), or maybe dark green & black - I'm sure I've seen this somewhere this season , would we acceptable options for me:
Also quite like this one as another option with Navy rather than black.