I think your approach to this is probably correct, the art change will inevitably be jarring but not something that can't be overcome, writing is like 80% of the total marks here.
For whatever this might be worth I would be willing to contribute to a Patreon for the game if it were set up, and I agree with the commenter who suggested doing this sooner than later, though admittedly there may be complications to this I'm not fully aware of.