As far as the HQ/Sig/etc walkthroughs go, just listing an Quest's name, level and where/who starts it is enough. We can get the walkthroughs from the web, but we don't know to get them if we don't know they exist.
The convoluted quest lines like Claymore and Greenhoods might be nice in the IC rather than trying to piece them together on Allakhazam or TTHammer. After opening up 4 or 5 pages of 'related quests' it's enough to say screw it and stick to the simpler quests.
The harvest info is vital. Nothing I hate more than zoning somewhere using spires, boats and wizzies to find out that what I want is not there. The cookbook goes hand in hand with the harvest info. I know exactly what to make and what I need to do it, and where to go to get ingrediants.
And I do make use of the Notes section but without table cappabilities I just suck at making notes.
And the worst... not backing up my Notes folders before updating the mod.
Btw, I've mentioned my wife's lack of familiarity with UI's and mode pieces before. I don't think she would even know she had an ingame browser button unless she accidently clicked on it. For ppl like her (and there are lots of them out there!), the IC is vital.
Sacraed