I came up with these as a proposed summary of sorts. I think we’re on to some similar ideas.
Magical Affinities - Thornmouth Summary
I love your totem suggest, a link to the time would make it easier and maintains the Time Travel rule of thumb that to go to the future is harder than to the past.
I’m not sure I follow your link to weathermancy, could you maybe explain that one more?
Regarding astral thinking and second mind I do wonder if these are more separate classes of magic, or if as you suggested and second mind is a subgenre of astral thinking. I wasn’t really sure how or what astral thinking is but your description of second mind sounded very similar to descriptions of astral projection.
I don’t know… I feel like the affinities listed are categories(or at least Thornmouth they all seem like different areas to me).
The guild has an affinity for science, and various members specialise in microbiology, astral physics, quantum theory. Or the guild has affinity Astral thinking with members specialising in different areas of projection, eg out of body(OoB) in current world, OoB and into anothers body, OoB and into memories. OoB and into alternative dimensions.
Does that make any sense?
Your second mind description reads like a speciality/specific application of your astral thinking description.