I've got a few nit-picks that I would consider to be Apple's low hanging fruit for the iOS 6 update.
The first key item that always annoys me is how Apple has forced 3rd party devs to store in-app content. I listen to lots of audio books for when I am on the road. Often driving 2-3k miles at a time. At the same time, I will have my iPhone connected to a wifi hotspot in the car. Which means that I can get Photo Stream updates or other app purchases that will automatically install.
The issue occurs when large swaths of data decide to get sync'd automatically. Apple has decided that, for example, Photo Stream files will get precedence over existing in-app data. Such as audio books. So, on my last long road trip I intentionally cleared off lots of space on my phone in an attempt to mitigate the likelihood of my audio books getting deleted. But, I had failed to realize one key detail: I didn't turn off auto-upload of photos on my iMac. While driving, and listening to part one of my book, my iPhone was silently downloading gigs of photos. The next day, when I went to listen to part two, lo and behold it was not there and I received the lovely message that I was out of space on my phone. Suffice it to say, I think Apple needs to do something to improve where developers can store downloaded files. Other apps should not have the power to delete files without discretion. I should be prompted prior to anything being deleted without my express permission.
Which leads me to my next pet peeve. iCloud. And I really mean Photo Stream. Although I do wish documents were handled in a manner akin to accessing a document in a Dropbox folder...
So, Photo Stream. As I alluded to above, I have a couple of Macs. One for work (MacBook Air) and one as my desktop at home (iMac). I have my iPhone that I use for both work and personal use. Let's ignore any iPads for the sake of simplicity.
I like the auto image uploads from my phone going to iPhoto. It's great! But, it needs to be smarter. Maybe location based? For example, if I were taking pictures at work, I should be able to configure Photo Stream to recognize this and only transfer photos to my Air. If I am at home, then go to my iMac. Things get dicey if we're travelling. The same goes for uploads from the full fat computers. I don't want pictures from my iMac getting sync'd to my laptop - it doesn't have the space to be honest (300 6+ MB images at a time is a lot of space!). However, I do like them going to my iPhone (if it weren't going to delete my books!) as I know they are automatically scaled down in resolution.
Currently, Photo Stream is an all or nothing. My iPhone can either get all the benefits of Photo Stream or none of them. iPhoto can either upload all or nothing (it can receive separate from the upload). I'm not certain how to cleanly solve this without requiring a very manual process. But, we should be able to turn off automatic features, but still allow for manually sending photos to the stream. Or to be able to direct which device will get the pictures (and I am well aware of being able to sync selected photos in iTunes - but this doesn't help when working from an i-Device).
So, these seem like relatively easy items to resolve in iOS 6. Improved handling of Photo Stream configuration and a safe location for apps to store downloaded content. I hear Apple is supposedly working on some sort of photo sharing capability...