How about people with color blindness?
one word: colorblind. i promise you all this looks quite different to my screwy eyes then to others.
Thank you for reminding us.
I would suggest a two-fold way:
Display some graphical representation of the address, any of the ones posted will do (as long as it works offline too!). As this has both color and symbol/pattern in it, even "colorblind" people would see a difference in many cases.
Display the first 4 and last 4 letters of the address too. This both helps "colorblind" folks as well as make (close) collisions of the graphic less likely. Depending on the graphical keyspace it could be too easy to generate the whole set once for addresses the attacker controls, and then replace the valid one with one which has the same or similar symbol. This might not be possible with 8 additional digits per symbol, but I didn't calculate through it..
Ente