Escalating timers are an antipattern. It punishes anyone who looks away for more than thirty seconds - and thirty seconds per click is not exactly a brisk pace for maintaining attention.
Other than that, good shit, well done. Undo was a welcome surprise. Ditto the repetition prevention.
No wait, one other thing. (Complaint sandwich!) Scaling should be in integer powers. Everything but fully-zoomed-out and extremely-blown-up looked lumpy and distracting. Especially with all the pixel art going on.