One thing I REALLY want is ALL ATTACHMENTS AS ICONS, and in a standard 'attachments' field, like ever other sane email client does. This 'render everything inline' and 'put attachments at arbitrary places' is so, so, so annoying and stupid. Please tell me this is fixed in Leopard.
I'd like to see a user preference about this. While I do like the way Tiger Mail handles attachments, I also understand your point of view. There should be a checkbox for this! You have submitted feature request, haven't you?