Allright. First of all:
I feel sorry but none of the shields you showed us here fits, except shapes and maybe the second Norman one. The first Gaelic shield is pure fantasy showing a Celtic cross in one of it's modern variations.
You're right. Reenactors tend to do what other Reenactors did before, so they just copy wrong stuff. That's ok, cause most Reenactors don't claim their recontructions to be 100% historical accurate and most of them are not historians or archaeologists. If we're looking for historical accuracy we have to search for those few Living History groups who work on museal reconstruction based on historcal sources and archaeology.
The "Hand of the gods" is originally from a small brooch. I've that brooch, bought it five years ago in Wolin and I'm not sure if we just can put this on a shield. On the other hand I don't know enough about Rus, but normally it's a common mistake (by Reenactors) to put just small art (from brooches for example) on big shields. That's fantasy.
Yeah, that's the point. More simple designs for Vikingr, Engle and Goidil.
Now my two cents:
Some new shield designs and banners would be nice, but please - don't add any ornated animal (Tierstil I-III) or similar fantasy stuff like Thorshammer-Banners. We have actually NO (!!!) proof for the use of that kind of small art (pressblech, brooches or jewelry/pendants) on textiles, shields or banners. Sources like the Bayeux tapestry, Stuttgarter Psalter or similar historic books with paintings may give some ideas about simple shield paintings with geometrical themes and stuff.Exception should be clanbanners as we use them now to identify unique warbands
I also can imagine some real nice angel paintings the Rus shields for the higher classes. And don't forget the difference between a representative shield and a "one-way-shield" for battle in real life. Just my two cents, pedantic as allways
And hey - there are and were mods with similar time setting in the past who used a ton of fantasy-thorshammer-shields and stuff. Ugly as hell. Hollywood-Style.
By the way, I guess I've some material for Möckerkalfie I won't post here for copyright reasons.