Get rid of casters entirely and use leg levelers.
As the name implies, you want to adjust the machine to 'level' because it has a sloped floor directing condensation down to the drain.
Instantly your machine will appear much smaller, plus you can always keep a $30.00 2 wheel dolly handy in case you need it from time to time.
Ha! I thought I was finally at piece with that decision and now you’ve got me doubting it again! Either way, is it difficult to swap the right rear one?