Burning questions about the Ring's symbolism and leitmotifs

1. What do the two Ravens represent? 

2. What does Loge represent? Aside from the God of Fire, is he the God
of Lies, the God of Truth, the God of Thought, a combination of the
above, or none of the above? What is the connection between any of
these, if any? I find explanations by Cooke and Donington to be
implausible.

3. Why do the Rhinemaidens and the Woodbird have a common motive? (It
shows up when the Rhinemaidens sing, "Weia! Waga! Woge du Welle!")

4. Why do Loge, the Woodbird, and the Ravens have a common motive?
(It's a rising chromatic figure and a series of trills that appear in
The Rhinegold when Wotan says, "Endlich Loge! Eilest du so...")