You put a lot of thought and effort into this.

Terrain art and other assets look good.

Nifty use of Krastorio assets.

Like the idea of using pump jacks to get steam.

Glad other modders made mini "scrap" in their resource chains. Just remember the recycler is unlocked on Fulgora.

Should consider at least one infinite research or other pay off. For example

The military planet Castra has ammo productivity.
Gleba has plastic productivity, rocket fuel productivity
Corrundum has alternate recipes, pressure lab, infinite research speed, novel way to do quality cycling.
Cubium has cube flexibility, bulk crafting, and alternate recipes.
Frozeta has science pack productivity, frost immune inserter, and an extra belt capacity, and a steam recycler.

I see that you force the use of foundries and include lava. If you ever change your mind about requiring Vulcanus/foundries, remember to
data.raw.recipe.carbon.alternative_unlock_methods ={"your planet discovery/intro tech here"}. That recipe for carbon is unlocked during Vulcanus

The planet's hazard should be apparent, if any. If you go for environmental hazards, consider using a global effect on the surface.

Consider a pay off that meshes well with other planets. Like what tech here would help - not outright replace - resource gathering on other planets.
Like a computational assembler, which would be a larger, techno assembler. 5 module slots and bit better base speed than a level 3 assembler.
Or bring in the programmable inserter from Krastorio, if allowed.