I hear what you are saying, but for me he was an important transition from singing players like Tal Ben Haim to your Yaya Toure's and David Silva's pf this world. Basically we had gone 30 years not competing at the top table going back to players like Steve Daley, Trevor Francis both who at the time had been wanted by pretty much all the major clubs
The reason most people especially outside City see him as a failure at the club(I recently saw a video on YouTube that listed him as City's worst ever signing! honestly I can name 30 without thinking about it!!). This perception, in my view comes about for two main reasons the media was desperate for City to fail and Robinho was the first prime target(you only have to look at the abuse Yaya got in the media after signing)and secondly Hughes used the media to cover his own shortcomings as a manager, our away record sucked because we had a lazy Brazilian in the team, when in point of fact our away record sucked with whoever Hughes put in the team and to prove that point he then moved to Fulham and their away record sucked too!