Molten Quiver

Next to the plain Magic Quiver the only new trick is turning Wooden Arrows into Flaming Arrows on the way out of the bow. By the time you can build this you almost certainly have better ammo sitting in a chest, so the upgrade is thinner than it looks. The pairing that does make sense is the Endless Quiver: the arrows are free forever and the conversion gives them a small bump they would not otherwise get. You lose the ammo saving in that combination, but there is nothing left to save.

You can wear more than one quiver and the ranged damage from each adds up. The extra arrow speed and the chance to recover ammo do not, so a second quiver is paying full price for one line of its tooltip. The velocity bonus also does nothing for arrows that already fly at boosted speed, which covers most of the special arrows worth firing.

Bows that already rewrite wooden ammo into their own projectiles, Eventide and the Bee's Knees among them, get no benefit from this at all. Their transformation happens first, and once the arrow has stopped being wood the accessory has nothing left to act on. Bows that convert any arrow type still hand you the bonus.