Well, a few days ago, I realised this could be a huge task. But then I remembered that Minecraft started out as Minecraft Classic.
And Minecraft Classic is quite simple (apart from Multiplayer)
(I realise lots of my inspiration is from Minecraft. I don’t want to make this game a Minecraft clone, but when I think of it as Minecraft, it seems like a smaller task, so I attempt to get things done quickly)
I noticed that as soon as collision detection and a few other things were working, I would only have to add content to get to the level of Minecraft Classic (Singleplayer only). Then I would be free to call it a game, and add whatever I felt like without worrying about ‘scope creep’ as the game to me would already be done.
So, I decided this morning to sit down at my seat and do the maths for collisions. And it worked (apart from the lack of wall sliding 
I was so inspired, that this afternoon, I got something else cool prototyped:
Player Models. :o :o :o :o 8)
(btw, that’s not the final player model ;D)
AND: a third person camera mode (WIP. Has a fixed distance. Needs clipping).
To avoid making this post too large, I will post a more detailed plan on my blog shortly (possibly tomorrow). Definitely tomorrow.