+ 2D PCA from Academic papers gives only very approximate picture of population relatedness. G25 on the other hand creates coordinates in 25 (!!!) dimension which is much detailed information. Pops that looks close on 2D can be very different in G25. One such a case are the Imeretian Georgians and Armenians.
+ When comparing ancient samples to modern one must be very cautious in interpreting data. One must also take into consideration archaeological context. Inferring linguistics from such a comparison is even more speculative. I just propose to compare Yamna to modern ones, You will start to think that they were Udmurts. Or compare Sintashta to modern ones You will understand why many Indians hate the idea that Sintasht Andronovo are Indo Iranian. Neverthless this is becoming mainstream in Western Academy.
+ Here are two tools for making Your own PCA's using G25 sheets.
Linguistics is something that can't be easily ignored. Let's not forget that current mainstream in West is that Armenian and Greek are related. Clackson expressed a different opinion but he's opinion is not widely accepted. The only reason why Andronovo is believed to be an Indo Iranian culture is the linguistics, because a lot off other data are going against that idea.