Great work! “KISS”.
But be careful, I used bearings on the holder of my Anet A8 back in the beginning times for hard filaments - with TPU it worked at the beginning, than there grew a slope between the spool and the printer. After some minutes, the slope was heavy enough and the complete spool unspooled itself on the floor…
I ended up with creating a little “brake”. So the tension was the same, regardles of the weight of the spool.