would an Italian describe Russian group of barbarians as light?
And you got the answer :D
alans were probably diverse looking people who assimilated various non-iranic tribes during their migrations. I think the orginial alans were predominately r1a like other scythians or sarmartians but they assimilated a huge number of caucasian people when they settled in the caucasus. Alans more in the north and far away from the caucasus had probably more r1a and were lighter. Alans were nomadic people and nomadic people often incorporated defeated tribes into their own tribal confederations. So many alans had probably also caucasian ancestry and some tests have shown that medieval alans carried already haplogroup G2 like modern ossetians. Haplogroup G2 is in this case clearly of caucasian and not of iranic origin because the oldest iranic people were almost entirely dominated by r1a and haplogroup G2 is very common among non-iranic caucasian people.
After the turkic and mongolic invasion most alans were either killed or assimilated by turks. Only the few alans who stayed in more mountainous regions survived this genocide and here they again mixed much with caucasians so that only few of them carry r1a today
It shows war between the Scythians and Persians who tried to conquer Scythia.
There was also war between Medes and Persians when Persians under Cyrus attended to take the power over the Median Empire. You probably never heard of "Brotherwar"?
Let me remind you on the Ottoman/Timurid wars. So going by your logic (if you ever had something called logic to begin with). Ottomans can't have been Turkic, right?
I don't know of any study which has yet published Scythian or Sarmatian aDNA. But what I know is eye and hair color is not a sign of DNA. ancient WHG people were dark skinned while modern people of pred. WHG ancestry are light skinned. The first ever Steppe invader from Hungary was genetically in between North Caucasians and Ukrainians ending somewhere in "no mans land".
Taking into Account that all Indo_Iranians have a good chunk of ANE as well ENF and signs by Lazaridis that earlier Yanmaya people where like West Asian farmers and Northeast European H&G. I doubt that they had no close genetic connection to North Caucasians. Allot of people speculate 35% ANE 45% ENF and 20% WHG. Thats roughly in between North Caucasian and Russian DNA. Don't take modern genetic landscape of European Steppes as representative of ancient Steppes. The Steppes today are heavily affected by the Slavic(European Steppes) and Altaic(Asian Steppes) expansions.