So, since Wick has a lot of his background relating to living off of bodies of freshwater and childhood stories of Ackleberry, and I'm rather new to Lusternia, I'd like some general information on Mother(?) Lake. Temperament, values, tendencies of followers, etc. Oh! Any other information on Ackleberry fae would be greatly valued as well. Thanks guys!

Tolborolla has some information directly related to Ackle! Their quest in particular has you meet the River Daughter.

It's Sister Lake/Daughter of the River and though I don't remember where, I've heard something Waterfall (?).
You can see, in Hoopah Hopekeep's home, that there are pictures of Undine, so they're presumably one of the Ackleberry water Fae.

If you read the histories, you'll find that Lake is equal amounts awesome and cool.

More specifically, the impression I get from Lake in the histories is that she has a very strong sense of morals and has a bit of a "heroic" streak. She put herself between Night and Sun, when the latter was hyped up on soulless juice in an attempt to protect her sister.

The River Daughter always begins her speech by reassuring the congregation that Ackleberry is fine and sends greetings towards them, so I also envision her as empathic.

Yes, She is indeed full of win. And kindness. And love.