Yes, suggestions and bug reports are very welcome.
I plan to keep developing it for a long time and add as many features as technically possible as long as they don't break the actual game play.
I don't want to add any functionality that makes it possible to cheat the challenge, that is why there is no pause.
But I see the need to be able to skip images too so I'm thinking about adding that without making the game easier.
Maybe replace the skipped image with a random duplicate of one of the other remaining images or distribute the skipped strokes evenly to all remaining images?
I'll probably test something like that in one of the next versions and see how it goes.