I think the current options are great, as is the alignment dialog used to deploy them. The only thing I don't like about the alignment dialog is that it eats global shortcut keys (e.g. align something and change your mind, you can't Ctrl-+Z to undo unless you click in the document first). A small niggle.

I'd love it if Xara added an "Abutt" option to the alignment tool, as a lot of what I do is mock layouts of gui's and games, where this would come in handy.

In case I'm using a weird name for this, what I'm talking about is selecting multiple objects, and then transforming them horizontally and/or vertically so that their left/right or top/bottom edges touch.