Really nice start! I've been enjoying modal editing in Vim. One of my pain points is that I feel like I don't have a lot of control over which buffer I'm closing when I :bd or what will happen when I open a new file when selecting it in Nerdtree. Sometimes it replaces a buffer, other times it splits the window. Im sure it's me not understanding how vim works, but I seem to get the mental model in Vico a little better. Bravo!