Another good informative review, thanks Ali!
The red/yellow colors are quire accurate to the dyes available to the Mongols, so I don't mind the colors being the same as the 4926 Easter Egg Mongol. Indeed I haven't had the opportunity to get my hands on 4926 yet, it hasn't been released where I live and I'm not paying triple through eBay, but I'll be getting half a dozen of each when I can, and customising some. I hate paying for an egg I don't want anyway, I'd rather have the figure without it.
The katana is indeed a strange choice, I'd have gone with a scimitar, though the Mongols did use different styles of swords, some with just a small curve at the end not dissimilar to the Playmobil katana shape.
I hope that when the full Playmobil Club is up and running we can address questions about these design "flaws" to Playmobil and have reasoned explanations.