ronaldinho is currently one of the best footballers in the world. Talent he has. Football brain he has. However, depending on where you play you may tend to perform better than elsewhere.
la liga is notorious for having defenders who are not defenders.....and this is converted to their national team which is why they are the most underachieving team in the history of european football.........case in point, the entire backline of real madrid, and before that hierro, when he was captain of spain. the culture is that of attacking football, so the space is provided for such. in the premiership, a zone defense is played, so there is similar space. the serie A and the bundesliga, however....different story. only the best of the best can cope with playing in all leagues.......luis figo, zizou, klinsmann, maradona, ronaldo....to name a few.
ronaldinho has the potential to become one of the greats as well.....but he needs to change his style to adapt to any situation. he can make waves in the premiership. he is already in la liga. he can perform in serie A but not with holding the ball that long....he needs to develop his game further, to release the ball earlier, and to greater effect (a la zizou)..... bundesliga......no chance. not with his current style anyway.