On the hands, just a slight difference (length one way or another) looks off against the backdrop of the dial. To me anyway. Again, most don’t even know until someone points it out and then it’s all everyone sees.
The hour hand, when at the 6, 9, 12 markers, should just ever so slightly touch the marker. =< It is especially noticiable when it’s at those points. But as I said, most people don’t even notice it until it’s mentioned. This was evident in the ARF V2s as a batch got released with the short maxi hands that were fatter and shorter than the hands normally on a sub. Many many many people accepted qc pics and wore the watch for a long time before ever realiz8ng it. Only then did it become an issue. And of course the problem is solved with a set of gen hands.