The Maxie and Archie in Team Rainbow Rocket are from a different world to their ORAS counterparts. I suppose Giovanni recruited them through the ultra wormholes.
I responded to you yesterday but my reply has disappeared for some reason... I actually came across someone on ebay selling all 8 of the Shining Pokemon cards early. I asked him about the shiny pull rates and he responded saying that they are rarer than regular holos but easier to pull than...
It hasn't "been that way" with either of the previous +1 sets... they have both received full-art supporter card promos (Hau and Olivia) which didn't appeared in the actual set lists.
I'd have to agree, both the full art variations are super boring that I don't even attempt to collect them anymore. HOWEVER, a rainbow rare Ho-Oh would be really fitting... it even fits Necrozma's theme and concept quite quite nicely in my opinion, with it being the "Prism Pokemon" n' all...