Not sure if that is a question that can be asked. I mean if you want to follow and support a club, you should be going with your instincts. Choose the one you have the most feelings to, the one you feel closely affiliated with. To answer your questions: 1. From what I know, I would say Athletic Bilbao's stadium - San Mames. Has been known as the most intimidating stadium in Spain apart from probably Camp Nou and the Bernabeu. 2. Not too sure about Athletic Bilbao and Atletico Madrid but I know Valencia is building one now currently, would be known as the 'Nuevo Mestalla' and it will be a 75 000 seater stadium. 3. Not 100% sure but think it would Atletico Madrid. 4. Tough to say. Atletico Madrid have won the Europa League twice in the last 3 years. Athletic Bilbao reached two finals this past season but came up short. Those 2 definitely have the potential to win trophies under Simeone and Bielsa, who both just took over Atletico and Bilbao respectively this past season. Can't say much about Valencia just yet. Will be under new manager - Mauricio Pellegrino next season and gotta see how they'll do under him first.