I have read the whole saga at least six or seven times, I am very confident in stating that I am one of the series's most hardcore fans, but I have no idea how people do not understand that there will inevitably be changes and differences to the characters. Otherwise, we would have no chance of this ever making to television.
Lets be absolutely clear. NOTHING that the tv show will do can take away the experience that we have based on reading the books. That is the most important point. However, it can absolutely make history in regards to fantasy tv shows if it is executed correctly. This has potential beyond GOT or even Witcher. The show has good thematics, varied character backgrounds, no single "more important than anyone else" protagonist (and I will debate you to hell and back if you think Rand is the only one that matters in this show, which is soooo not true.), and it has so many complex, powerful and competent women too.
It can lose some of its Robert Jordan-esque "oh, all women are controlling, all men are mules" mentality, and the base concepts of Wheel of Time can improve tenfold. Also, and I cant stress this enough, I absolutely think that one has to be very sheltered to truly think that a city cant have a cultural cohesion with people of different skin color coexisting. It absolutely can. And there was an influx of refugees and different skin-colored babies too when the Aiels crossed over to deal with Laman the Treekiller.