It wouldn't be based too much on user complaints or metacritic scores for SimCity or any other game really. Underperforming revenue is likely the largest factor in Riccitello's departure. There has been a string of quarters hitting below/low on their outlook.
To Riccitello's credit, EA was in a terrible position pre-recession. A bad business plan, an inflated stock price and a bloated portfolio. JR had to make some brutal choices during the recession and has turned EA into a leaner beast, banking on online distribution and focusing on a smaller, higher quality portfolio.
And while the big picture of where he took EA is a logical one, I assume that the missed revenue from underperforming titles is the biggest factor in him stepping down. Of course, this is all conjecture on my part.
EA's business plan has been the same since the early 90s.
Step 1: Forcibly sodomize both customers and dev studios.
Step 2: ?????
Step 3: Profit.
In all seriousness though, I think that to make the company leaner, they were forced to abandon many franchises and platforms that they found to be unprofitable. The shitty part about this, is that if the business side of EA didn't insist on ruining the majority of the games that EA makes, many of them would have actually had a chance to stay profitable.
There have been numerous occasions where the features of a game don't match what has been printed on the back of the box.
Also, look at the Sim City fiasco. The people who purchased it couldn't even play the game in many cases, because they weren't able to connect to the authentication servers.
Of course, remember, this is EA - to them, Dead Space, the most popular survival horror franchise of the last five years, underperformed.
Still, I doubt this has much at all to do with SimCity. If it does, it has more to do with its low MetaCritic score than actual user complaints.