I've logged an item in the project tracker for this. I think the hierarchy needs to remain based on the sort order integer, but what I think we could do is have a button that would resort child pages of a given page alphabetically. 

Best,

Joe

fyi, this is now implemented, there is a new icon/button in the Add/Edit Pages (aka PageTree.aspx) that will resort the child pages of the selected page alphabetically. You can try it on the demo site now if you like.

So this will be in the new release coming soon.

Best,

Joe