I’m with you on this one - I didn’t like the friction. My older machine was the more traditional style (the print heat moved in both X and Y, and the bed lowered for Z) and too much filament tug would not only result in the filament slipping, I’d even lose Y axis steps and my prints would ‘lean’.
With the enclosure (you didn’t mention if you have one) it’s even more friction since the filament also routes thru the enclosure side hole / grommet.
As someone else mentioned, bearings (I used ones for rollerblades at first) barely fit over the shaft. Another option is a printed roller support kind of like this one (print 4 of the spheres and the one um…‘support’ 
- from there it should be obvious - the holes for the spheres might be a bit oversized but I got a 1/8th stainless rod thru there and then used a gel superglue to affix it at the ‘open’ end only, be careful not to glue the balls to the rod as you want them free-rolling…)
spoolmount_rollerball_ball.stl (357.3 KB) spoolmount_rollerball_ballsack.stl (96.5 KB)
I’d also STRONGLY recommend a filament guide of some kind. When the machine goes ‘home’ sometimes the filament pops over to the wrong size of one of the Z rails. Here’s an image of mine, it’s too big to upload here as a file for some reason (probably all the blends). If you want I’ll upload to Thingiverse or there’s others available. You might remix the one part to extend the ‘loop’ a little longer, it’s worked for several prints for me so far but I keep thinking I might reprint it, eventually.
OH I should add, if you do go some sort of bearing or better roller route, watch at first with ‘full’ reels for it “freewheeling” too much and popping loops over one side of the spool to get trapped between the spool and the support arm. Definitely a problem with too little friction, but in my book a far easier problem to deal with. I am still paranoid and just don’t let my printer print unattended 90% of the time.