Quote Originally Posted by Dimers View Post
Pretty much any secondary benefit from an Expertise will rely on your power/feat/equipment choices, and most of them can be quite handy in the right situation. Staff Expertise happens to work for more situations, so that's the top of the heap. I'd consider Tome the best of the more specific ones -- well, maybe right after Flail, but certainly before Light Blade. War Wizard, Orb, Bludgeon and Devout Protector can also be strong.

IMO the only Expertises with always-weak secondary benefits are Axe, Heavy Blade, Holy Symbol and Polearm.
Are you considering the axe benefit weak because it can be replaced by a brutal weapon? Personally I thought it was a pretty cool bonus, but I have not played too extensively.
for ref:
Axe Expertise
Benefit: You gain a +1 feat bonus to weapon attack rolls you make with an axe. This bonus increases to +2 at 11th level and +3 at 21st level.
Also, when rolling damage for a weapon attack you make with an axe, you can reroll one damage die that results in a 1, but you must use the second result.