You're thinking too literal, especially with the Game Center icon. The name already implies games. But unlike the Apple designed icon yours does nothing to convey the role the cloud plays in bringing players together.
Design can be both simple to provide necessary information, or more complex to also include an emotional connection as well. A good example might be Toyotas logo. I doubt many people realize that it's intent is to
"symbolize the unification of the hearts of our customers and the heart of Toyota products. The background space represents Toyota's technological advancement and the boundless opportunities ahead."
I can't say Apple is more or less successful with there attempts, but I suspect this approach is a prime reason for some of the dissatisfaction expressed on these boards.
Just my opinion.
While I do agree that icons such as Game Center are perhaps a bit too literal, and that specifically Game Center doesn't convey the app's purpose well, I'm not changing it.
The general consumers don't tend to appreciate images for their deeper meaning: they recognise them simply for their face value and consumers just use the image as a way to identify a specific brand or app or whatever. Apps such as Safari do have icons that have meaning behind them (to navigate the web, for example) but are also easily distinguishable and recognisable which is what makes the icons 'successful'.
My problem with Game Center specifically is that while it does in ways have deeper meaning behind the icon (the bubbles overlapping represent bringing together players) the image itself is not recognisable enough and just doesn't stand out against the other icons.
When designing an icon, I feel the image's ability to stand out from the crowd is slightly more important due to the fact that's what the general consumer tends to appreciate more. The controller has some relevance to the app, but importantly will be recognised.
And let's face it: designing an app icon that's distinguishable, relevant and meaningful is difficult. In my opinion, Apple didn't succeed with Game Center.
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Have you considered making the colored panels a little translucent, like Apple did with theirs? That might look nice. Or it might wreck the aperture look. It would be interesting to see, though.
I think it will be difficult to pull off a fully flat design with Photos that also incorporates transparency. And I think you're right in saying it could weaken the aperture effect of the icon.
And that you can't do transparency in MS Paint
