OSR Figuring out a favored terrain-esque class design?

I dusted off my old Witching Grounds setting – I ran 2-and-a-half D&D campaigns with it, wrote a short story for it, and have a bunch of messy notes – and finally decided to decouple it from the modern D&D rules that I'd been trying to mash it into like a round peg into a square hole. The setting is a blend of dark whimsical fey themes, Welsh lore, Arthurian lore, Etruscan lore, and general weirdness. Right now it's of a mashup of B/X, touches of AD&D, Beyond the Wall, a bit of DCC, Dolmenwood, and a bunch of my own stuff. The classes I'm writing are quirky, things like the Clogstomper (a warrior with wooden shoes, dancing, and a touch of magic) or the Crook-Errant (a wandering guide/shepherd with a talking sheep companion named after a shepherd's crook).

I'm trying to figure out a feature for the Crook-Errant that is akin to the ranger's favored terrain: Well-Trod Lands. The idea is that it offers a general benefit for all terrains, and then a specific benefit for each of the 6 terrain types which does some combination of (a) benefits the Crook-Errant PC, (b) benefits their party, and/or (c) benefits their sheep companion.

That's what I could use a hand with – how to tailor the feature to each terrain type – either your own ideas or pointing towards resources that might be good inspiration?

Full class writeup (rough) is attached as pdf & jpg, and what I have for the feature so far is below:

Well-Trod Lands
As a crook-errant travels they learn the lay of the land and its unique features. At Levels 2, 6, and 10, the player chooses one of the following land types they have visited to be “well-trod.” They always treat pasture and grasslands as “well-trod.” While traveling a “well-trod” land, the crook-errant and any small company they lead are surprised only on 1 on a d6, and reduce any traveling speed penalty through that land by one step.

1. Bogs & Fens: ##
2. Burrows & Caverns: While underground or in a cave, the crook-errant recognizes which creature lairs there (if any), and their sheep always finds fresh water.
3. Coasts & Saltmarshes: ##
4. Henges & Hills: The crook-errant recognizes when they enter a henge that is enchanted, or a hill that holds buried dragons or sleeping giants.
5. Mountains & Dales: Within highlands, the crook-errant is immune to altitude and alpine herbs allow their sheep to heal all its hit points during a rest.
6. Woods & Wilds: ##

I became very disillusioned with ranger benefits being only binarily operational in their favored terrain (+x to y checks but only in the favored terrain). I would much prefer the terrains or favored enemy stuff be connected to a thematically appropriate style or power that is always available though maybe most suited to the terrain. For instance a sea theme sailor might have climbing for going into the rigging but it would be applicable to climbing trees or scaling walls too. Forest terrain stuff might have an herbalism option.