I'm not interrested about his "idea imperial" or by anything HRE-related for now but more about how he changed the spanish government and how it lead to the revolt of the communeros.
Bonus point if sources in spanish
I'm not sure what exactly you are asking for. Charles V first came to Spain only in 1517, along with his tutor Chièvres and a group of Burgundian courtiers, consisting of many Flemings. The Revolt of the Communeros started in 1520. Between 1517 and 1520 there were many significant assignments of leaders from Charles' Burgundian contingent, and requests for revenue from taxes, but there is no mention of organizational changes.
For example, Chièvres was appointed contador mayor (and later sold it, much to popular anger), a post that had existed for centuries. Cisneros was made Regent of Castille prior to Charles V's arrival, but that's to replace Ferdinand II of Aragon. Adrian of Utrecht was given a Bishopric for his services. Charles also sent his brother Ferdinand -- who grew up in Spain and was popular there -- away to Germany almost as soon as he himself arrived there. When Charles weakened the Cortes of Castille, it was through bribery and placement of agents who are his allies, notably Jean de Sauvage.
Following the conclusion of the Revolt of the Communeros, there were significant reforms, however these are done after the revolt, not before.
Source:
Another recent book to examine is Aurelio Espinosa's The Empire of the Cities: Emperor Charles V, the Comunero Revolt, and the Transformation of the Spanish System which argues that Charles V was able to form a pragmatic power-sharing relationship with Castile's municipalities after the Comunero revolt.