Ok my character is an arcanist who is a seeker of knowledge. He has left on his heroic journey to find out about the world. He is constantly taking notes, drawing sketches of what he sees, etc...
Alignment NG
Right now I have him marked as a follower of Nethys, but not sure if that is the most fitting?. Who would you suggest and why?
Follow me!
...Wait, no, I don't take NG followers.
In that case, Zohls is the LG Empyreal Lord of Determination, Investigation, and Truth. That seems close.
A race-specific god might be more appropriate; what is he?
How are you with elves? There is a magic+crystal focused elven god by the name of Yuelral that fits that bill.
He's an elf
I am planning on going into a Divine spell casting class as well (Well maybe, still debating on his long term plan, but Evangalist and Mystic Thurg are both very appealing)
Perhaps a god with the Travel domain if he want's to go about and learn through experience.
There's also a few more Empyreal Lords that might fit, depending on the exact nature of your character (in no particular order): NG Bharnarol, of inventors, persistence, and creativity, CG Sinashakti, of journeys and messengers, NG Soralyon, of monuments and magic, and NG Eritrice, of uncovering truth.
I honestly see Desna as a solid option here, assuming freedom is a big deal to you. She does travel, the night sky, freedom and such
Nethys has the advantage that you're far likelier to meet other followers of the god than of some empyreal lord, but the evangelist boons mostly aren't terribly useful to you if you take that path.
If he sees beauty in knowledge and is at all artistic with those sketches Shelyn might fit. Better boons for you than Nethys but not great.
But yes, for an exact match one of the empyreal lords above would probably be best.
Irori. God of perfection with knowledge as a domain. His devotion gives +4 to all knowledge skills.
Join my church. We're very lax about hygiene. Takes the pressure off. They even named a cheese after me.
When all else fails, Sarenrae will always welcome you.
Follow me!
...Wait, no, I don't take NG followers.
In that case, Zohls is the LG Empyreal Lord of Determination, Investigation, and Truth. That seems close.
I second Zohls, taking sketches is literally what you do as part of her Celestial Obedience.