Not 100% happ[y, so some slight changes will me made:
Not keen on the parallel sides coming down from the rear light past the number plate light. I'll reshape a little to loosely folow the outline of the lights...but not too much. I don't want to remove much strength from the area.
I don't like the fact you can see the indicator securing nuts/wiring, so giving that some thought.
Don’t forget that A) a coat of satin black will negate most of your points and B) no one will ever scrutinise it that close up !
You can get rubber boots that cover the nuts, Rizoma indicators come with them, I’m sure a search would find similar. IMHO that would be enough to neaten them up. Trying to hide them with more steel etc would seriously degrade the simplistic elegance of your current design IMHO.