Working LCD Driver

So I got my LCD driver to fully work this morning. Some bits of it are sketchily set up though due to no memory management. Heres a pic of what it looks like now (drawing from a buffer):

So I guess the only thing left to do with the driver (which I will put off for now) is to create a partial update function that only updates a region of the display (when the whole display is updated, there is a visible tear which can hopefully be fixed through partial updates).

I'm not exactly sure what I should do next. I guess the possibilities are: memory management, hard disk access, graphics api, kernel & threading. I think that text output would be a good thing to have. For this (unless I come up with a better way) I would need to have bitmap font loading from the harddisk and likely memory management stuff as well. So i think that I should get the memory thing done with and then hard drive accessing and then bitmap blitting / fonts. Since I'm not very familar with the implementation of thread schedualing, having text output would probably speed up development in that area significantly.