Well of Eternity is an Ouroboros as you said, except with a dragon instead of a snake, to mirror the official icon for Heart of Thorns.
Also as you said, Well of Precognition with an eye to resemble clairvoyance. It also bears resemblance to the Eye of Fatima, which has been traditionally donned by those claiming to be psychic due to its connection to the Ajna Chakra or “third eye” (the area on your forehead that’s said to be the source of psychic vision)
As Embolism stated above me, Well of Calamity proudly displays the Death’shead Hawkmoth, which has been seen as an omen since ancient times of both madness and incoming disaster. Madness to reflect the obvious references to sanity/insanity in the Mesmer profession, and disaster to reflect the tremendous damage this well causes. Even though this particular one is a moth and not a butterfly as typical for the Mesmer, its kinda cool to think about the fact that butterflies are associated with mental illness, as they are often said to reflect some deep aspect of the human psyche from which madness originates. Also, the more obvious reference, Butterfly Effect.
Well of Action and Well of Recall used to make more sense; Well of Action used to immobilize foes, and Well of Recall used to spin fully around the clock 3 times when the spell gave its Alacrity first and ended with chill on the final tick, where the frost-burst effect happened. The fact that it was speedier than the other clocks was intended to visualize the applied Alacrity buff, which was effectively “fast-forwarding” time. I actually really hope they change the visuals on those two wells to more accurately reflect their new incarnations.
Gravity Well, if you look closely, actually depicts the solar system.
Mesmers are so incredibly clever in their design, its just one of the many aspects of the profession that makes me love it so much as well as the creative minds behind it. It’s all very subtle too; in your face, but simultaneously subtle. Very Mesmery when you think about it.
I like