fbeazer (I'm going to try to get out of the habit of quoting so I'll respond in order). As I understand things...
The edit button is still there for a bit if no one has responded to your posts.
The formatting buttons are available if you click the Enable BBCode Editor button at the top of the reply window.
Same with URLs and IMG links
dunno anything about the Gravitar thinging but I think it only applies to sites who are linked to Gravitar.
My Posts gives me every post sorted by most recent to oldest -- dunno why your's doesn't.
Reply All is not the same as Post Reply. Think of nested posts. Reply All is at the same nesting level as the first post on the thread; Post Reply is in response to a particular post and would show up as nested within the post if there was nested viewing.
Go to your Preferences (My Posts or Topics, then Edit Preferences) and Expand All Posts to Yes so that you'll never have to use the fit button again.