Here are some more pinned down stuff that isn't just more of the general stuff I have been finding- hope these help in anyway they can :D

• Dwarf Fortress Wiki - Even though this is mainly for the players playing the game, using the advanced world gen is basically modding the game with how clunky it can be. Though not everything might be needed or could translate looking at the variables used and how the systems interacte might be a good reference if you are aiming for something.
• Unity Forum List - This list has some asking about terrain generation
• Blob Gen - a small blog talking about a way of doing biome gen using blobs. It has animated gifs too so that's cool
• Unity Forum List 2 - This list has people talking specifically about biomes
• Random Biome Generator - This just has some biomes that will be picked when you click the button, though you can do multiple at the same time if you want to try and combine 2 at the same time in a drawing for practice or inspiration
• Math for Game Developers
  • Tile Based Stuff - This talk is done by a cave of qud developer and it seems to use something that's relatively new, and it seems to do texture based stuff from the mapping and seems pretty cool
  • Overview of Procedural Stuff - This talk is done by I think a caves of qud developer, and I hear people like that game so it don't hurt to try and yoink the bits of it that you like from this talk
• Blender Stuff (I know you kinda got used to blender in the last update, but practice makes perfect and you may need it for making structure models anyway)
  • Blender "Hacks" - they really are just tips, but there is 200+ tips in this video so that's pretty good
  • Export Fundamentals - in the description of this video there is an overview of the stuff in it, so if you are still dealing with stuff (like the rig bones being bendy/stretchy) it may help if you need help exporting and you can just look in the description for the specific thing
• 10 tips for clean code - may have already seen this video, but it might help to remember so you don't get spaghetti code when working on the biomes
• Old random minecraft 2017 about dungeon generation using command blocks. - Well my last link might as well be a bit silly, but feedback to different games could always be reflected on if you think about it. Also I just want to show that minecraft permeates it's way into every online discussion because I can.

Hope these are nice, for you and for others, also anyone can feel free to put more resources under this topic so you won't have to all the links in your suggestions (if you do that and just want one link to one topic)