I have a big wishlist:
-Proper hierarchy and pivot points
-Mesh colliders with prefix (like for UCXes)
-Mesh LODs with prefix (like Unity)
-Objects animations
-Vertex animations
-Automatic lightmaps assignment for composed meshes, and not limited to only one
-Better vertex snapping inside of editor
-Node wire pins in material editor like we have in blueprints
-Materials Layering
-Opaque glass material
-Shadows from translucent materials (even like from cutout only and very approximated - you can see that in Stingray Engine already)
-Cloth Editor
-System for character skeleton definition (like Unity Mecanim Humanoid, but customizable)
-Character Root Motion template
-NPC AIs examples for all templates
-HUDs examples for all templates
-River and cascades tool
-Day timelapse and weather with rain and snow ready to use, properly integrated with Editor + no rain, wind or snow volumes (for interiors)
-Vector field editor for particles
Those things would make us all soooo happy 