hello again,
1. Seville has 22,000 searches in UK but very few people look for Sevilla.
2. It depends, I prefer subdomain.domain.com instead of subfolders.... I only found English language at your site. Even if you use /en/ you need a main language (that could be English), and this is not necessary to have the subfolder: www.domain.com (for English), then www.domain.com/es (for Spanish).... and so on. But well is a personal decision ![:) 🙂](https://moz.com/community/q/assets/plugins/nodebb-plugin-emoji/emoji/android/1f642.png?v=4jds23d1a2r)
3. OK
4. You didnt get my point. Please read my message and my example carefully (since I checked your site carefully). It's very very important you dont repeat similar or same keywords in the same URL. In my example before it was "Seville+Sevilla" and "university+universities" in one single URL.
5. Again, the best is to have the minimum subfolder as possible! URL like this: www.eurasmus.com/erasmus-seville-city-guide are much nicer for Google than www.eurasmus.com/erasmus-sevilla/city-guide
You can keep only one if this is your strategy, or both since they have different content and context. It's up to you and if you apply a good SEO strategy I dont see any problem having two pages.
About the long tail, I already explained before. You are maybe ranking now for non-competitive keywords (study the keyword difficulty rankings for your pages/keywords) for those pages. I recommend to focus on why you are not ranking well for the pages/KW you want and optimize your strategy.
Hope this helps!
Luis