Translation of artillero

It all depends on the language that you want to learn. For German it would be best to go to Berlin, as the pronunciation is classic there. Imagine going to Switzerland where they speak a different language.
Yes, but on the other hand, using full, simple sentences also helps people who are learning the language more than just the short clauses. It is probably a mix of both, but I have not decided yet which ratio is the best for us.
These may be linguistic and cultural differences. There are indeed various regions throughout Spain and the word choice is not always the same. It is sometimes hard to understand people from other cities.