If you decided to not go with Katana's as the prime weapon, but went more with a Naginata. Kind of like how alot of grey knights use the "halberd" it would look much better. Also you would need a near complete redesign of the armor. The "plate" look just simply places them as a European style as compared to just about anything else.
That and Tau definately have that "layered, segmented" armor look to it. Now if they could just learn to do more than thier limp-wristed hth they might be worth it. Think about if all the firewarriors could use that Etherial "combat blade" they might be actually halfway decent
For every battle honor, a thousand heroes die alone, unsung and unremembered.