Gear sensors have the greatest benefit for less experienced riders. That being said there have been times on difficult technical trails where my GS has checked me when I was more focused on the terrain than backing off while shifting
Not sure if you were asking purely for the hub or for lack of braking power on your ride but...
A second hand suspension fork with disc brake mounts can be found on ebay fairly cheap.
2 birds with one stone if your running a rigid fork currently.
Potholes at 20+ mph are a bits less scary...
I do this on my motorcycle on long rides and used to do it as a messenger on my non e-bike. The potholes really do discourage you quite quickly though. Unless your riding a large tire bike or are on pristine roads you will likely encounter the same thing.