Lukas,
in what way is the arrowroot-sized papers more difficult to handle?
FWIW:
Ammonium chloride is supposed to give slightly faster printing times and a shift towards a red-brown tone, according to what I have read.
A fifth method, is using a mix of beeswax and oil of lavender. The oil of lavender is only a vehicle to help apply the wax and it will eventually evaporate. This gives some contrast and a satin finish. France Scully Osterman was kind enough to give the details of this. I can't vouch for its long-time archival properties.
I haven't tried either of them (yet). So if all it does is crash and burn, don't blame me!