well i was thinking about this when i have played Starbound. The player will be gathering minerals and crafting ammunition... for the entity mineral destroyed player will gain points. The points u could change in a forge into weapons, ammunitions, items etc... the monsters will be respawning just like in System Shock. There would be cold enviroment where the trigger_hurt damages player. I would enter the player into a story line too. He will be finding ancient technology, abandoned data disks, logs, mails. There will be a space ship with a command room and and there will be a big map texture on the wall and u will be able to push a button on it and get teleported into a planet It would be more like a mod where u travel throw the maps and explore level design, discover the history of current planet than kill headcrabs and cook them. I think it might be interesting experience to create barren locations. The textures won't be a problem. There are a lot of resources on cgtextures.
what do u think? is it possible to do all the crazy stuff without coding?