I assure you, you're not crazy. On the contrary, counterfeiters are getting better and better at imitating, and you have to be extremely fussy and vigilant to identify copies, whether of cokades, plates or chinstraps. By definition, they are 'reproductions', and so they copy the authentic ones... identically. Fortunately, for the time being, careful and suspicious examination still allows us to distinguish the real from the fake...
As far as helmet plates are concerned, on the whole I always try to get at the back, and in particular the fastenings and welds. At the Epernay fair (France), I saw a Chapska of the UR7, the plate was absolutely undetectable from the front as a copy. It was stamped to perfection.
Concerning the eagles with banners:
---0fficer: still a "Koenig" eagle of the line, with banners attached and soldered with tin.
---Enrolled group: After the Kaiser's AKO of 1899, the eagles already on the helmets of the active regiment (Waterloo, Peninsula, Belle alliance etc...) had the banners attached and soldered. Subsequently, however, the newly-issued helmets were fitted with new plates stamped in a single sheet of brass or nickel silver.