Just a quick question I couldn't answer with the help of the manual:
Can I be sure, that the querys are executed in the same order as the list of parameters are provided and the next query is only started if the previous has ended?
Yes, the operations are performed by the server in the order they are provided. Note that cursor.executemany() cannot be used for executing queries. It can only execute DML statements (insert, update, delete) and PL/SQL.