Chiming in on the aosmification of the Clanrats. Skaven, as with Lizardmen and possibly Chaos Dwarfs, are a few of the armies which to me were already High Fantasy in WHFB. I always felt those 3, and I guess Daemons to an extent, kind of already stepped outside of what WHFB was.
Lizardmen and Skaven really feel like they belong to the Realms because their Aesthetic has always been, pretty Eccentric. But that could very well be to just to my mind and eyes. Remember we all perceive Things, including warhammer, Through entirely different experiences and attach our own notions and experiences of film, literature, art etc. Mine has always been that the Steam Punk Ratmen that used magic stones of pure magic to create Electric Weapons and telephones to be quite the oddball in the Warhammer World. Same went for the Inter-dimensional Space Toads/Lizards.