I think that there are simple and yet far more effective ways of displaying and grouping quests.
First, I think the player should have the option to collapse the quests in the quest log, down to a single line for each. The important details of the quest like "defeat xxx" or "collect xxx" and the location showing up in the description, and a "+/-" sign available for you to expand the quest to see either the picture or the quest dialog. I think showing 4 quests per page, and making us scroll through is a bit tedious, especially if you have many quests.
Second, and maybe to supplement the first suggestion, is to group the quests by world. Maybe off to the left, there would be a list of worlds, and you can click each one to see only the quests in that world. This could be a drop down, to save space, and should have an "All" to show all quests if desired.
Lastly, a simple "quest count" to show you how many quests you currently have.
Thank you for taking the time to read and post on my topic.
Quick Bio: Hi there. This is my first posting in the W101 forum. I'm an "older" player, coming from other serious MMO's, and I now play W101 with my wife and teenage kids. Wizard 101 is a wonderful game, and in the few years that it's been out, has continued to grow.