I'm not sure what about it seems "German" to BCAC. It's a Sherrifmuir doublet, which is a fairly traditional style of Highland attire. One normally seems them in black barathea or velvet, but there is no reason not to have one made up in other colors (as scotchmaster here has done). I think it looks rather nice! I, personally, probably wouldn't have chosen the facing under the buttons, but I also withhold judgment not having seen it in person.

I had a Sheriffmuir doublet made for myself in grey Harris tweed. I think it can be interesting to play around with a "formal" style doublet made up in a less formal fabric. It can seem to limit the occasions one has to wear it, but whenever you do it will be noticed!

I've seen that particular style of neck treatment (can't really call it a "tie") offered on another web site, and I have to say I don't really like it. However, it seems to work well with that outfit, so kudos!