Creative Improvements

Sandbox in my perspective seems to lack some features to benefit users who prefer to experiment with blueprints given it lacks some Quality of Life Improvements that can be beneficial for sandbox.

I can recommend a few improvements:
* Make the buildings and items you already unlocked available to the sandbox
* The upgrades can be changed within sandbox instead of being stuck at max level
* Make the dye mixer usable as doesn't have the pigments powders
* Add pigments of the color variants once you get the blue pigment
* Add a way to access the challenges parts.

The reason of the suggestion was to make schematics much easier to produce without space constrains even before/after you get the blueprints research to save on resources and time plus the pigment part would be neat have variants of such colors to the dye ones.