Level editor?

Can someone make a level editor in the viewport , BPY?

ideally this kit would produce pieces any game engine can use.
(based on a grid and reusable geometry pices)
Kit = pieces made using very few materials and atlas textures
Map = like running a 3d building game

You tag objects in a (Kit)scene,
That are then used as instances within the level editor?(Map)

like tremulous buidling system but for making maps?

Make a map -> press a button and all the instances are joined into pieces based on a grid?
(for draw call batching?)(only pieces that are close enough? and use the same materials?)

I want to make levels for my game, but I am easily sidetracked by other tasks, and for
workflow etc, this is a big missing piece.

while someone is at it, can they add in a flag for lamps (replace with light hook?)

(populate the closest 15 spot hooks and 15 point hooks or(set by user))
My dynamic lighting manager works but could still probably be optimized .

with a system to load theses maps dynamically (by seperating the chunks into seperate scenes or?)

and The dynamic lighting manager,
Many people could make a shell of the level thy want fast, and then generate the map, and have systems like doors, be easy for newbs?

I can provide a system for interacting with the doors, and I can even provide examples of logic based action handlers and pythonic ones,