Don't worry, I really like your work and the GRIM setting has hooked me since I read the preface. If I may make a suggestion about what you just explained, I can think of another way to approach it. You see, as the system is based on D2 rolls, the advantage could be successes that make up for failures and in the case of the disadvantage it would be the opposite, failures that make up for successes, for example if I want to attack a group of Walking Graves and due to the situation I have a disadvantage of 1 and I roll 3 dices, let's imagine that I have 2 successes and 1 failure, then that 1 of disadvantage would turn one of my successes into a failure and in the opposite case if I have an advantage of 1, then that failure I get in the roll would be a success. This way you separate the re-roll mechanic as if it were a new opportunity to try your luck and the case of advantages and disadvantages as something more inherent to the situation of the PJs. I hope my idea helps you to continue with this great project!