Atletico Madrid has a very competitive squad and Ismail is high there but I think he can be a rotation player. That's why I also think the German league or the Portuguese league would be more suitable for his development. Because the training level of Turkish players and the training level of Spanish teams are very different. Players who go to Spain can suddenly flounder because there are much tougher and stricter training rules. That's why if Ismail chooses to be a first 11 player instead of a rotation player, he can choose a team in Germany or a team in Portugal.
Ismail Yuksek isn't even the best player in Fenerbahce, but his quality is higher than his market value, that's the reason why many teams interested with him. Since he's not the best player, he should rotate to other position, who knows that his potential is on other position instead of as a defensive midfielder.
If he move to Benfica or Marseille, the competition is nothing different than in Fenerbahce, he should get out from comfort zone.