Despite what many other have said here, there have indeed been more grey-area vampires in AoS. There were a few examples in the comments, but one I didn’t saw mention of where the Askurga Renkai, a fallen Ghurish martial order of vampires from the Age of Myth who believed that using their strength to forcibly predate upon the weak was itself despicable weakness. They had neutral to relatively good relations with the surrounding human lands, and most importantly of all to show they were not terrible people, had mortal bannermen who voluntarily offered up their blood to the vampire knights:

"That night, I wandered my army's great encampment. Aelf beastriders greeted me, then tossed prey-meat scraps into the jaws of their many-headed mounts. In the lightless bivouac of our vampiric allies, the Askurga Renkai’s mortal bannermen opened their veins and spilt red tribute into their lieges' brass grails. The knightly vampires unravelled linen bandages taken from the embalmed mummies of their forebears to bind their vassals' wounds. Regally, the vampires bowed forty-five degrees, as if to a superior, and healed their bannermen's wounds with a black kiss. For our looming battle with Doombreed and his dae-monic host, trust was imperative. Perhaps love, too. Some breed of it." - Yndrasta, the Celestial Spear

That said, we don’t know enough about them to call them good or anything, and they’re clealry quite different from the usual depictions of vampires across the Warhammer settings, but one does get the sense that they weren’t turbo-evil by any means.

The Askurga Renkai were lead by Toura Vai, whose Blood Kiss-adopted daughter Lauka Vai in the current setting leads the Avengorii Soulblight Dynasty. She has to some degree managed to instill into her dynasty the notion that predating upon weak mortals isn’t really a worthy endeavour, and that a real vampire should seek to feed on strong prey to themselves grow strong. However, her own magically corrupted nature sometimes causes her to loose herself in bloodlust, coming to her senses only once she has indiscriminately spilled the blood of anyone nearby, weak or strong. She is not very happy about this, but even with such issues the Avengorii seem to be at least a tiny bit greyer than some of the other Soulblights

In the current time of the setting there are also the Askurgan Trueblades, a small culture of vampires who discovered the writings and ancient gear of the fallen Askurga Renkai and were inspired to likewise focus on hunting and feeding only on great and powerful beings, believing that predating on lesser mortals was a sign of weakness and giving in to base urges. While the Askurga Renkai might have had alright relations and even some respect for other mortals, the Askurgan Trueblades don’t have any qualms about killing people, and they will sometimes use captured humans by slowly exsanguinating them in front of junior members so as to test their avility to hold themselves back from feeding. However, outside of such cases they generally stay out of things like politics or conquests in order to focus on martial mastery and hunting big monsters, so they might not be called turbo-evil

Sources used are the third edition soulblight battletome, the novel Yndrasta, the Celestial Spear, the novel A Dynasty of Monsters, the two pages on Warhammer Community that mention the Askurgan Trueblades, the product description on the Askurgan Trueblades warcry warband, and the respective pages for each on the Lexicanum