Science Fiction-based rank devices, outside Trek TOS and, to some extent, TMP has always been too small and/or somewhat indistinguishable from one another.
The whole point of rank insignia (in the real world, anyway) is to easily differentiate who you need to salute to, or from whom you would expect a salute, from a good distance away. Fletcher's TWOK-era insignia does a serviceable job until you get to the flag officers, then it gets a little murky.
And don't even get me started on NuBSG. Not only are the devices virtually indistinguishable from one another at a distance, but the costuming department constantly screwed up what devices went with which grades.
Trek TNG tried to get back to a TOS-style rank system, but with pips instead of braids, which could also be somewhat difficult to see from a distance, especially if there was a blacked-out pip stuck in there somewhere. And I especially disliked how non-officers were handled in the TNG era. It wasn't until O'Brien became a regular higher-tier character in DS9 that a non-com grade finally got the respect of having its own device - a first, I think, since Kosinski's odd-looking device in "Where No One Has Gone Before".