Long story short, I'm looking for a replacement for the mod listed since the original mod author took it down following the train wreck that was the Frontier? Does anyone have good recommendations or a list of mods that can replace it?

Hi there !!
There are some substitutes, but not as extensive as the one you are saying. 
You can have Book of Steel/Water. 
ADAM for NCR ranger/desert ranger/riot armor. 
Spice of Life (used it, didn't like it as much as Wastelanders Clothing Hires honestly... but like you said, sadly it was removed), this should be the most similar one to WCH, sadly you have to mod your game a bit further.
Also there are plenty Overhauls made by dragbody posted here.

In general you have to go and look a bit to see what really catches your eye, both here and on the nexus page there are a ton of mods for clothing and armor (armor mostly TBH). Hope I was able to help you a little bit at least .

Posted twice like a dope so ill share another good retexture of combat armor

The Gruntening - 2k Combat Armor Retextures

I actually like this one apart from book of steels despite it being old and having no helmet textures alongside it

Charge's FNV HD Texture Packs is a good start and base as it also has a section that divides upscales of all armor, clothes, creatures, dlc, and weapons in the game. even covered some that were left untouched by the mod you listed