CoC First Edition divided skills into categories and assigned a bonus to them derived from the relevant Characteristic. So for example Manipulation skills received a bonus from Dexterity. I always quite liked that system.
As regards skills, I think Charm, like Dodge with DEX, should start at half APP. Own Language allows for improvement, particularly for characters who write for a living. Thus my journalist characters for the magazine Strange! But True roll their Own Language skill when they write an article. If they succeed, they have written so well that the crusty old editor pays them a bonus.
Lore skills to me a specifically non academic, non mainstream. They represent the 'oral tradition' kind of knowledge; the things that you don't find written down, or only in the most obscure and private sources. Generally I tie them to a location - eg. Innsmouth Lore, or an occupation Seafarers Lore.
I like the idea of Field as a humanities type counterpart to Art/Craft and Science. One early skill I would revive in that would be Linguistics, with the attached possibility of a character having some knowledge (say 1d20%) of any particular language.
Skills I would specifically include would be two from Trail: Contacts and Preparedness.