No, that'd make their overlap with kithkin too obvious. When people say that dwarves are is more due to their focus on tradition and structure, not on the bonds between community.

The dwarves I thought of, for example, would be more akin to, say, what the Dromoka are to Selesnya or innistradi humans. Communal and group-focused, yes, but with a heavier emphasis on the dogmatic side.

To be fair, Nin is part of the Izzet League, so maybe it's more of the guild's influence over her than an expression of her inner self. Though the Flavor text does imply she enjoys her work.

Nin isn't ravnican.
You can tell because she has 4 arms.

Somone just said she was because Ral referenced her while talking about other Izzet members. Also this guy.

Also, you note 1) he's simic and 2) that "mutant" bit in his type line.

Yes, but his graft seems to be gills if you look at the larger art. The arms look like you would expect from most four-armed Vedalken.

I find it really funny that you pulled that up but didn't read the article it was from.
The article was about the fact he had four arms when nobody else did.

To be fair, I just Google Image searched. But fair enough.

Exposure to aether appears to cause an extra finger and hair though.

I assumed that four-armed vedalken are like 6-fingered humans. It's a rare genetic trait, but in a small population it could conceivably become the norm.

they're reportedly supposed to be vaguely froggish, so it's a common mutation to generate extra limbs specifically.