At the top of my personal Missing list is an Adjustment for All Attacks.
There are so many things in 4e that do a conditional or temporary bonus or penalty on all attacks, and the only way I have to track them currently is to put a Temporary Adjustment on the Weapon or Power (there isn't even one for Implements) that I'm currently/about to use and try and remember to change it every round (because I like to use the Powers panel for reference instead of endlessly switching between the In-Play and Specials tabs).
(For that matter, it there a way to put a general attack bonus into a Power? If I could do that, I could automate Dragonborn Rage.)
An Adjustment for all non-AC Defenses would be nice for the same reason, but at least there's only three of those to adjust individually as opposed to a plethora of Powers.
(While I'm wishing, it would be nice if the box about not needing the downloader anymore would go away, but that's just crazy talk.
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