What you can do in FFF is limited. All of that, given the network errors, is really outside of FFF's direct control.
Given the reports, I agree that it is possible, even probable, that AO3 is throttling users in some way--which is honestly their right.
slow_down_sleep_time as previously discussed, adds a sleep between network requests.
Inanis, I suspect you're putting
slow_down_sleep_time in the wrong section or something.
Another key setting for AO3 specifically that is on by default is
use_view_full_work:
Code:
[archiveofourown.org]
## AO3 offers a page to download the entire work at once. This can
## save a lot of network traffic if there are many chapters.
## True by built-in default.
use_view_full_work:true
Turning
use_view_full_work off will cause
more network requests--one per chapter, but fewer database hits per network request. If AO3 is throttling by network hits, turning this off will only make it worse, but it is something to be aware of. IE, this is why total download time isn't at least sleep time X number of chapters for AO3 downloads.
With AO3 you also have the option of downloading an EPUB directly from the site. So if you have troubles downloading with FFF, that's always an option.