I fell in love with this project the moment I set eyes on it, and I will be thoroughly impressed and happy when it's finally done. However, I do have a couple of questions regarding certain aspects of the game.
1 - Will we be able to have control over the generation of certain aspects of our worlds? What I am asking is, will we be able to, for example: add humans into the world or create our own races altogether? I remember in your preview videos you mentioned that humans and other high fantasy races might have to be modded in, but could it be possible to give the player the option of developing certain species to their specifications? I would love to see this feature because I would be able to guide the development of the world to suit my play-style. As much as I love alien worlds and what-not, I also would like the option to make that world have that touch of familiarity, so that I may feel more connected to the world. I'll be the first to admit that I don't know a whole lot about coding, but, hopefully, a feature such as this wouldn't be too hard to implement.
I intend for the player to be able to do these sorts of things, yes. I'm not *EXACTLY* sure how I'll implement that yet, mostly because there are still some big segments of history and creature generation that need to be built upon once the game engine is looking more sturdy, but I'd like for people to be able to insert premade races and such with relative ease (probably just by copy-pasting some definition files, many of which I'll include as optional material for people who want it).
2 - How will you handle aspects regarding magical elements? Will spells or magical practices also be procedurally generated? Will certain things like alchemy be present in each world, or will these aspects also be procedurally generated? Also, will the game procedurally generate magical symbols, if you add such things at all? I am rather curious about this, because I am always a mage when I play fantasy games 
I think spells and magic will be more akin to those in Morrowind. The 'stock' spells will be procedurally generated, but a trained mage character will be able to create their own customized spells via some kind of spellmaking interface. Spells/abilities gained through the worship of a deity, on the other hand, will all be completely procedurally generated, and will probably not be customizable in the same way magic is (although they may well be very potent in comparison with most types of 'normal' magic).
3 - How will the ethics, laws, architecture, etc. be handled in civilizations? I would assume that the customs of each civilization will be procedurally generated, but what about architecture? Will each civilization use pre-made architecture, or will it be procedurally generated? If it is the latter, how will these buildings look in-game?
All procedural, eventually, yes. I had already considered procedural architecture to be one of my goals, and I have quite a few thoughts on how I want to implement that. I don't really want to say too much yet, though - mostly because I would enjoy showing off the results tangibly with a video or images much more than writing about the concepts here and spoiling them.
I will give away one small spoiler just for the sake of teasing, however: if you see a procedurally generated architectural design you like, you'll be able to copy it directly as a blueprint into the building system and replicate it with just a few clicks wherever you'd like to build.