And not forgetting the fashion in number plates that have varying degrees of shade so that they look almost black (I assume ANPR defeat).
Various adjustments to the fonts with fake 3D effects
Spacing and screws eto try and make personalised plates out of shite
The "display plates" that are completely illegible.
I believe all of the above are illegal but people will rarely be pulled for it because the police simply don't have the resources.