Just a quick Voynich thought for you (I’ve been typing all day and my fingers are tired, so apologies for keeping it very brief) .
On f86v3, have you noticed how the two spotty, side-profile beak, wings-outstretched birds are almost identical? Apart from the fact the one on the right here (which is in the bottom right corner of the actual page) has some kind of heavily-inked line in front of it, and that there’s a faint line behind and to the left of its right wing. (Click on the picture for a full-resolution version.)
Furthermore, the vertical lines just to the right of the second bird are in a much fainter ink, which is a bit reminiscent of some of the balneo section drawings I’ve discussed here before. This leaves me with a lingering suspicion that this page may (once again) have been executed in two passes – a first layout pass, and a second obfuscatory pass. Don’t know what it all means, but it’s interesting all the same. 🙂