That sounds like a good plan.
PfsAIO is the preferred file system, but it has a maximum safe partition size of 100GB (probably a little less). That has a sector size of 1024. And do make sure you get the latest version from Aminet because that's the one that is friendly with 3.14.
The reason is that it doesn't need validation every boot, and is much more reliable in cases of power failure combined with disk writes (FFs usually corrupts when this happens).
tart
Having a 4gb max partition at the start is useful for programs that only work when loaded from that area.
However, in terms of a bootable Workbench partition, that can go anywhere. It doesn't have to be at the start of a disk. And you can select a different boot medium from the early startup menu (holding down both mouse buttons on boot).
You can have have multiple Workbench partitions with different boot priorities, letting you select an alternative if the main one is not accessible because it's become corrupted through file virus or similar.
Don't expect to get it pecfectly right first time.
