Knights and cloacks are just a must have. I dont know what i would add for the samurai or vikings as cosmetic rewards.
But I think a cool cloack for reputation 20 or 30 for a elite appereance would be really cool. Cause the reputation rewards now are just boring af, already maxxed out gear and the outfits paterns are barely visable. So a cloack would do great.
What your thoughts on it
Cloaks would be fitting for knights. Albeit a bit unrealistic to run onto the battlefield with it being something that an opponent can grab onto and tug at for an easy stabby stab time. Samurai could get a banner to have on their back like you see in historical photos where upper-ranking soldiers would carry a tall flag/banner on their back into battle.
vikings I guess would do good with some pelts as a helmet replacement.