It's true, only a very naive person would say that any system is perfect and cannot be improved upon further.
It is also highly likely that increasing the base move speed by +5 or +10 will not cause any extreme amount of extra desync, however I would also argue that were it not for the numbers being available in the paperdoll you would also not even notice such a small change given that 425 to 435 is only a 2.3% increase in speed.
The result would be people moving very slightly faster, while being hit from very slightly further away in fights, and peoples movement on screen being very slightly more jerky / desynced due to the prediction being less accurate.
I've said it before, and it has been stated by others in this thread already, but my issue with things like this is if the speed were increased to a point where the people advocating for a speed increase were actually happy with it, the negatives would be too high for a lot of people to accept.
This is likely true because these same people were completely happy and content when we had 489 move speed, and saw no issue with it.
As has also been said before, I would wait until we get the correct racial and clade attributes to see just how fast a lean or even skinny veela will run by comparison as we don't have any confirmation on where this current speed will fall on the spectrum.
So at the moment it could potentially be a case of "I don't like how slow humans run" and not yet having the option to play a veela and run +10 speed faster.