For many of us, there's no real reason to work full-time, cutting your expenses and working less is great. Also: it's economically irrational how little time we spend optimizing our investments vs. our salary/work-skills (i'm still a sinner).
I'd say all the terms are wrong: you've covered maker, hacker also has nothing to do with this, as well as indie, which means being alternative, outside the mainstream. I believe you're looking for "Independent Developer"
I do something similar, but my flow is around feature branches: I create a branch, dumping TODOs in the code as I work out the feature, then progressively fix them before merging the branch. Wrote a little script to highlight TODOs created in current branch (vs base) if anyone's interested: https://github.com/yonilevy/branchtodo
Coincidently I just started working on a drawing app, specifically an iPad app with figure drawing as the main use case. If you could share more details on the kind of drawing you'd like to allow it'd be easier to help. In general, as others said, there's a big difference between vector and raster based drawing apps. In vector drawings, you need to capture the mouse/pen/touch input and fit the points to a bezier curve (google "An algorithm for automatically fitting digitized curves"). Then you have a bunch of bezier-curve objects and draw them to the screen, any 2D graphics library will support this. Raster based drawings are more tricky, you usually paint with a brush, which is a bitmap that gets blended to the existing drawing, possibly affected by the input (pressure, angle, etc.). Here your focus is on performing graphics operations efficiently, as there are many of them per second, and they should appear to occur in real-time. A GPU is very helpful to this kind of drawing.
Another big aspect of this sort of app is undo/redo support. Again it's gonna be different between vector and raster, but I find that in any undo-supporting app, figuring out how the undo mechanism will work can guide the rest of the software design quite effectively, so give that a thought.
If you're willing to share more details here I could probably help more concretely.