I searched Aminet for HFS+ file system entries and it doesn't seem like there is one that would work for the modern incarnation of HFS. I looked for ExFAT and there are some OS4.x implementations.
There is FAT32 but there seems to be some potential issues with directory length and disk size; in this case 128GB. Perhaps I am wrong about the FAT32 stuff.
Should I endeavor to make EXT2 work with my MacOS installation and/or Windows machines? EXT2 and EXT3 are certainly superior to FAT32 and there seems to be a driver for EXT2/3 on Aminet.
Thoughts? Has anybody used this with Trident4.4/Subway?
What is your intended purpose of the thumb drive?
For most versatility i recommend keeping the FAT32 fs.
If you aim for large files and data transfer between modern systems, NTFS will work in most these systems. with a little hassle it will work in a mac.
Making Windows system reading HFS or EXT partitions will be hard work.
Software like "get data back" will read and let you "salvage" files from a EXT drive. but usage will be severely limited.