+1 Dwarven Decapitator
Was 2h weapon in earlier versions.
+2 Sling Stone of Smiting
Interestingly enough the +2 Sling Bullet of Gazebo Slaying does not have text about to hit or dmg bonuses.
Amulet of Smashing
Second try at getting "when attacking" dropped as it's not in the rules to deal damage with a 2h weapon while not attacking.
Medallion of Keenness
This is way too specific. Just drop rare requirements. Consider that if someone has UR weapon or shield, probably going to run a different neck item, anyway. So, all doing is limiting people using commons, uncommons, and transmutes. None of those are a problem.
Necklace of the Songbird
No non-instrument token should add to hit and/or damage to bardsong. While there's plenty of ways to be more similar to prior versions, getting help from a Songbird could be thematically represented with +1 to saves or the like. Or, if want to make it spicy, "Adds '+1 to saves' to party's Bardsong bonuses". Who knows, that last might still see play with WLL builds.
Necklace of the Woodlands
Um. So, bracers can give +2 damage. Neck is better than bracers, in theory. Class specific token can be stronger than any class token. Note that the similar wizard token would be "+3 spell dmg" or the similar cleric token would be "+3 healing" or the equivalent druid token would be "+3 healing, spell dmg, polymorph dmg" (I can't resist). Would I replace an UR neck item with this? I'm not sure, which is scary when one considers how amazing UR neck items are.
Pendant of the Pure
Does the DR from this work the same way as normal DResistance in class ability? I guess so, since DReduction and DResistance are two different mechanics.
Robe of the Sage
Either add "damage scrolls" to this token or drop it from other token. Either non-damaging scrolls can deal damage or they can't.