said the man who also spent a lot of time with an unfinished RPG...
That's a lot more common than you might think. I used to work on a classic pencil & paper RPG, and planned on making a videogame out of an episode of the series, but never made anything for it (didn't last for 2 years, but still pretty long).
Planning game development is only useful for complex projects, and complex projects (such as RPGs) are usually best made by a group, where written plans help share ideas and establish rules. If you program by yourself, while others work on artwork only, you can safely leave everything in your head: it will still work out reasonably well and come out faster.
I'd argue that at the very least, instead of directly working on pixel sprites, you could still make character sketches; they may be useless for the game, but people generally appreciate concept art.