Hello again, Fugl devs! I just have a few thoughts kicking around in my skull pertaining to this title, so I thought I'd put them here in one place before I forget, if that's alright!

Nests
I have seen a recommendation to use nests as a sort of home base/waypoint in Fugl, and I think that would be a brilliant way to include some form of saving your exploration progress for the people able to generate terrain -- and also just a nice addition to having a bird. It could be set up as something we can generate with a keybind early on, perhaps -- but if ever things evolve far enough, it would be very interesting to be able to set them up by foraging for materials -- but that's much more work, and I recognize that!

Landmarks
I think... the addition of certain environmental elements could be very interesting, and would give players another reason to go hunting for things to find. An occasional structure here and there, whether it's an exceptionally large tree to a distant tower of voxels (perhaps one with windows to soar though?) would help break up the stasis of the environment, in my opinion. I don't know if your engine would appreciate elements designed to render in a certain way, however, so I understand if this is not possible.
That said, there are many options I think you could implement!

• The aforementioned overlarge trees could be seen in most environments, whether conifers in the snow or huge palms in the tropics.
  
• Tall structures like towers and pillars serve as good waypoints for navigation in addition to being a treat to stumble over.
  
• Whirlpools in the water would be fun to encounter (though I do wonder if escaping them would be difficult?) You could also add shipwrecks or big coral reefs -- the ocean is vast.
  
• Towns or other clusters of smaller buildings could be neat to fly over. If you found a city lit up at night, flying through that could be incredibly scenic (and maybe we could turn into a pigeon!) You could have so many architectural styles too as user generated content jumps in... someone could do a very vaporwavey future city with the colors of that one alien biome I've seen, or a rustic hamlet in the foothills of a mountain range... it would give the world character, and in a way, would help reaffirm that at the end of the day we're still just a bird flying around in this big huge world.
  
• Cave systems at ground level that open up into underground chambers could be an easy-to-miss, amazing to explore adventure that's sure to frustrate everyone who slams into a wall. (A bat morph would also go well here! Caveat emptor that this might already exist; I come from the perspective of someone who cannot generate terrain, so my apologies there!)

I personally feel that this could add a lot of depth into the world, if it's possible! And a lot of things could be created in the workshop by dedicated players as well if there was an editor for it!

Environment Interaction
I know every additional thing you add takes time away from improving the core mechanics! So I understand if this is a no go -- but the ability to eat fruit off fruit trees, or to pick up and carry small animals or objects away from where we find them, just because -- maybe even a button to make bird calls, just for fun -- would be really nice. It doesn't even need to have a purpose, it's just nice to have these little side-features to do!

First Person View
... Just because! If possible!

Achievements!
I saw a call for some in a thread that went unanswered, so I'll do my best to rattle off a few.

• Crash Landing: The first time you hit something.
  
• Maiden Voyage: The first time you hit the water, specifically.
  
• Spelunker: Something to do with caves -- spend x amount of time in one, or perhaps just hit a cave wall. (I crashed a lot at first, can you tell?)
  
• Reset: Reset the level for the first time.
  
• Something New: Transform into X creature for the first time, perhaps individualized for each one.
  
• Shapeshifter: Transform into everything you can transform into at least once.
  
• Cartographer: Once maps are available in the workshop, explore a whole map for the first time. (If doable.)
  
• Explorer: Discover "X", x being whatever you define it as in the environment.
  
• Publisher: Upload a creation to the Steam Workshop!
  
• Achievements related to game playtime, perhaps. Hatchling, Fledgling, et al.
  
• Maybe some more niche, unexpected ones. Jump the Shark for kiting a shark as it jumps out of the water, for example.

But I understand adding that many could... rapidly lead to achievement spam, so maybe not all fo them. But it's a start I think!

Clouds
Might tank performance, but having a world of clouds to soar through above the game would be nice. You could have big fluffy cumulus clouds and wispy cirrus clouds and dark forboding stormclouds, it could add a lot to the atmosphere of the game in my opinion!

Weather
Adding on to that... this is a pretty big one I think to suggest, but adding weather to the game world -- at least in some biomes -- would really add some dynamism to the whole experience. Some of it could be expressed in shaders, and some of it would have to be added as new assets I think -- I have no idea if your engine would tolerate it, because I know some of the minecraft mods for this purpose are very finicky -- and I know adding in the whole system could be a ton of work in the first place. So it's more of a "one day maybe, it would be amazing" kind of thing, in my opinion.

Speaking of,

Environmental Effects
Just things that would add to the game's overal aesthetics or appeal, that may not have any function beyond looking pretty... but aren't strictly weather.

• Someone suggested an Aurora for the artic biome... I want to add to that idea with the suggestion of LET US FLY THROUGH IT!
  
• Rainbows. If weather is a thing, they can be given a %chance to spawn after rain if the next weather is sunny, perhaps!
  
• Day/Night, with sunsets and sunrises -- and perhaps a starry skybox for nighttime.
  
• If possible, more shader effects to go with these changes -- but that's far down the road.
  
  Biome Sugestions
  ... Caveat emptor, I can't use the terrain editor at present, so if any of these already exist, I'm so sorry!!
  
  • Mountain foothills: low hills, lots of greenery, from flowery meadows to dense thicket forests. Also caves, small mountain streams, and random ravines are surprisinly common.
    
  • Mesa: Basically the Grand Canyon as a biome. Lots of canyons to soar through, weird rock formations, kind of orange.
    
  • Self-Indulgent and Unlikely: ....Big Vaporwavey, Cyberpunk-y megacity with skyscrapers and a lot of neon colors to explore. It would just be so cool!
    
  • Swampland: Marshy, flat and dull green with lots of shallow water and weird plants -- and birds!
    
  • Underwater Biomes: Not exactly sure how feasible this is but we could always turn into a penguin to explore craggy shores, coral reefs, muddy rivers, or the cool blue of arctic waters. Maybe even deep, dary, scary underwater ravines to explore!
    
  • Big Small World: A regular biome expect all the assets are bigger so it looks like you're the size of an insect. Not sure if feasible engine-wise. Lots of big blades of grass, huge flowers, maybe you can be a bee.
    
  • Coast: Like a desert adjactent to the ocean. Very rocky, lots of water off to one side, probably cliffs on the other. Ocean waves as a background noise and lots of seagulls about.
    
  • Volcanic: Volcanoes! Lava instead of rivers! Glowing embers in caves as an environmental effect. If nontraditional birds are permitted, a phoenix would fit right in.
    
  • Mountain Ranges: Super duper tall, likely resource-intensive structures, sparsely forested at best, snow here and there, perhaps. Maybe the occasional cave pitting the mountains. Lammergeiers would be a good pick to fly around in at this height.
    
  • Jungle: Densely thicketed, maybe vines to form partial barries to fly thorough! Probably a lot of green. Maybe some ruins to uncover... in all honesty the default rainbow bird is perfect here.
    
  • Cloud forest. Like a cross between a temperate biome and a jungle, they're constantly misty and would have a lower FOV and probably a cooler colorscheme overall. Cool lizards and other wildlife can be found there, too, a lot of animals make microclimates out of the bromeliads that grow in cloud forests.
    
  • Candyland-esque world: Lots of pinks, things that look like candy. There is no reason to add this whatsoever but it'd be fun.
    
  • Magical/Halloween-y Biome: ......For use of the color purple. Dead trees maybe, a little spooky but offset by sparkly things to keep it fun. Curled trees like in Nightmare Before Christmas, maybe you can turn into a ghost! It could be a lot of fun.
  
  Once I'm able to use the terrain editor, if ever, I'll probably have some more refined suggestions, my apologies! I saw a call for waterfalls though, and I concur! I can probably make tailored sugestions for each biome implemented as well once I get my hands on them!
  
  This... wound up longer than anticipated. I hope that's alright! I really like Fugl and I really do look forward to seeing how it's going to develop. If someone took the time to read this monstrosity, thank you very much! And if I think of anything else... I might just append it here, in all honesty.
  
  Thank you for reading!