The only one you need to play is Secrets of Whispering Pines, as is the first entry. Granted, there will be a moment at the end where the dev tried to retcon all his other works (ala Spider man No Way Home), so don't be too surprised if it gets a little confusing but its no big deal.
I'm pretty much the same, a couple of years ago I discovered Maou-sama, The Guardian and Secrets of Whispering Pines among others, which were very restricted in F95 or outright banned despite allowing things like Degrees of Lewdity or Insexual Awakening. I heard the discussion of this site and...
Personally when deciding favorites, I'm more inclined for the japanese VNs as they give you a complete product but some western VNs are real gems.
LIKE:
Dessert Stalker (Zetan) - You play as Stalker (very competent mercenary) in a dystopian world with Egyptian aesthetics. It's nice to see our...