The last major outstanding package is directory. The maintainer said they will try to update it in time for GHC-9.6. Until then, refer to my branch https://github.com/hasufell/directory/tree/AFPP
The only other package I will migrate myself is hpath, which will then probably be the first strongly typed filepath library that uses OsPath under the hood (current WIP branch is here).
That will be it from my side. Anything else is up to the community to do.
If anyone wants to get this into base (at least the type), you have my support. But I won’t drive that myself.