Your 'comic book', 'graphic novel', 'cartoon, 'pen', and 'sketch' on GIMP. G'mic filters.
The first 3 topics are basically alternate versions of 'oil painting' rather than something artists would pencil, ink, and color. Anything with the words 'pen', 'pencil' or 'sketch' result in muddled, incoherent messes that look nothing like what a user might have intended if they wanted to convert something to look like it was done by any of those. Even using all of the adjustments they look nothing like what artists might use them for. I hope you take this into account with your next update.