I have (just about) finished this, but feeling a bit dissatisfied with the very final part of the end game that involves erasing three letters. This is returning to questions previously raised by Foinaven. There are an obvious 3 letters to erase, but given the killer's fate I too would have expected what's erased to be plural. This is not helped by the fact that the same 3 letters also occur in a line elsewhere in the grid (albeit in a different direction), so the erasing could in theory be done twice.
Also, while I recognise that the more obvious 3 letters to erase still leave a real 3-letter word at the end, I'm uneasy about the words that cross the erased letters, specifically the middle one, where I'm not sure I would call what's left at the beginning of the crossing word (before the deletion) a "real word or name."
Finally, is there any significance/symbolism in the shape of what's portrayed by the highlighting/erasing? If there were, this might help provide some reassurance that I'm looking at the right 3 letters to erase.