@Gargron I've used a LOT of different project management tools over the years, all fancy in their own way. Also used notepads with coloured priority stickers.
The best decision I ever made was to scrap them off and just use a txt file. As soon as I know something needs doing, I add it to the file, most urgent at the top. Nothing gets forgotten, amends are easy, and you only have to pay attention to the top.
Fancy systems put too much focus on what you haven't done, and how tight deadlines are.