I'm currently building a Hypercube (CoreXY) and luckily caught this same suggestion on YouTube before I got too far. Have most of the parts printed, and started some assembly. Should have x-y axis moving this weekend.Something that I'd recommend if you haven't designed this way already is to use toothed idlers where needed. I've been very happy with the quality of the prints from my printer over the years, but there's this very slight surface variation noticeable on shiny parts. At first I thought it was extruder pulsing from being direct drive, but I switched to a Titan Aero and the pattern was identical (not 1/3rd as bad due to the 3:1 gearing). I tried a bunch of stabilization stuff or printing slowly or rotating the parts or loosening belts but it was always the same pattern. I took the time to replace the double flanged bearings on the rear corners and on the XY bar (only those where the belt rides on the teeth) and bingo problem solved. This was just this past weekend so I am pretty stoked about it still. I got the idea after seeing this guy post about it on thingiverse, although my parts don't have it as bad as this RyBot thing:2801046.
It's a real not-easy-thing to replace them once they are installed in the back corners so I'd highly recommend it during the build process.
I only use Esun PET, can get on Amazon. I print it a 240°John,
What brand do you use? I am just about out of the roll of Hatchbox PETG I am printing my C-bot parts with and Hatchbox is saying they don't expect more in until a few months from now. I love not having the fumes from ABS and having the parts be as strong as possible.