This is great! I was going to move over my old 3.9 install and "update" it - this will save me a lot of trouble! You, my friend, are a lifesaver!
Please be aware and cautious of the location I used myself though. SYS:Expansion is normally used by binddrivers to locate add-on hardware (reference: http://www.jaruzel.com/amiga/amiga-os-command-reference-help/binddrivers.html). Now, I am not affected by this, but it also depends on what hardware you got installed yourself. If in doubt, I suggest to hand-pick a different location and change the Assign command in Startup-Sequence to point to that other location.
*EDIT: off-topic, but for some more additional information about Expansion you can have a look here (https://wiki.amigaos.net/wiki/Amiga_Hardware_Manufacturer_ID_Registry.
I have 40+ drawers in my Expansion drawer. Binddrivers appears to safely ignore drawers and their respective .info files, so I think it's perfectly safe. It has been for me for years anyway.