This is actually something we have already commented on and see players regularly bring up. What our development team has been considering is to increase the number of characters that are allowed on each realm, but keeping the character limit per account in place.

This means that it may be possible to have just one massive list of characters on a single realm. No promises, but I would like to have all of my characters on one realm as well :D

Please remember that, in the future you should use the search feature to look for information on things such as this before creating a new topic on the matter, as I already touched on this matter here - http://eu.battle.net/wow/en/forum/topic/2868763386#5

Keep the constructive discussion up though guys :)