I know I said I was not going to talk about other services but iCloud is so integrated into iOS I really feel I have to include it. iCloud is Apple's latest attempt at a Cloud Service. The key function is syncing select data like Contacts, Calendars between devices such as an iPhone and iPad or devices and computers. It's not totally bad but like many things there's room for improvement.
Notes should really be detached from the email account. For users without Mountain Lion they could create a little Notes App if they like or just make folks go to the website if they feel that's too much bother.
Safari syncing bookmarks rather sucks. It would be nice if there was a way to 'mute' bookmarks or at least folders of them from either computer or device. Or at least a separation of syncing bookmarks and reading lists.
iTunes playlist, ratings etc syncing via iCloud without regarding iTunes Match would be useful.
Shared photo streams, journals etc. Our accounts can be used for a number of sharing items with 'public' web pages as an option. But those pages are all over the place. Why not a concise sharing page where all things are linked. Something like the old Homepage of Mac.com but built off our iCloud sharing and perhaps our iTunes reviews and playlists as an additional option. There might also be widgets that would allow us to put links to our Facebook etc or even an option to log into your own iCloud account to see private streams etc that you have been invited to see. If they do as I hope and bring back Lala.com this could also be linked into it.
Backups need some work. Right now the automated timer only goes off once every 24 hours, if you are plugged in and on wifi, but what if that is the middle of the day and you are in the car. Days could go by with no backup. After like 3 weeks you'll get a warning. A better timer system might be 24 hours after the last successful backup and 12 hours since the last attempted time that couldn't connect. Or even just every 12 hours. A best move might be to let us decide how often an attempt is made and how often we are warned about failure.
Along with better timing, how about better control over what is backed up. This could be done (although with the timer controls) in an Advanced Mode. In this mode, users would be able to turn off SMS backups either in all or limit it to say only those in one's contacts or only 'favorites'. Voice Memos is another item that currently cant be turned off. That could be all or set the system to know which have been synced via itunes to the computer and allow a selection for those since last sync. In a similar fashion, the camera roll could be set for all, videos only, videos and photos not in photo stream.
Going with better backup control how about selective restoring. One could choose either to restore everything or if you are restoring a backup from say a larger storage iPad/iPhone to a smaller one, picking off things to ignore like not restoring purchases, camera roll, certain apps and their data, and so on. Once the selections are made a choice could come up to delete the other data and continue this device or make backups after the restore a new device and require a new name. So for example, I've been letting my little brother play games on my iPad which I also use for email etc. But now I've bought him his own iPad Mini. He doesn't want to lose his game levels etc so I restore the backup turning off email, safari, camera roll etc. Basically leave just his apps and their data. And tell it that this is to become Toby's iPad while leaving Jaye's iPad with all the data separate (well until I delete the apps and their data from my iPad).
And speaking of app data, why not separate the data in such a way that we could keep the last backup of something even if it is deleted from the device and restore it later. So say if one becomes bored with a game and removes it for space the data is there should a second look be desired.
Recognizing that a device was backed up to iCloud seems to have some bugs in it. From time to time when one uses an iTunes backup to restore, it starts a clean backup with no immediate notice of the old one. That reconnect would be nice even if it was set up to require the owner to choose whether to do it or delete the old backups. And how about more than 3 backup dates on the list.
The last bit is visibility. When you log into icloud.com it should be possible to see details about everything. Not just Contacts etc but also bookmarks, reading lists, when was the last backup and what was in it and even let us delete bits and pieces to tidy things up. Perhaps even the ability (if the data was separated) to delete bits and merge the rest into one backup scheme.