That annoys me too, since I have a small screen.
Well, the header could be made smaller on all sites, not just the forums
It kind of makes sense for the front page, because there's not much more than the header on there. But for pages which are not about "hi, we are the guild", but about some content, especially for the wiki and the board, there's really a lot of spacing - even if one accepts the large picture on each site, there's some 50 to 100 unused pixels around it.
Would it be possible to make the header optional in some way? Like, for example, to only show it when the mouse goes to the top of the window, or to scroll down some 100px initially when loading the page, I dunno.
Or, if that's not possible, maybe merge the two headers we currently have everywhere - below the GoW header, the board has a totally pointless "Forum" caption, and the search bar. That "Forum" can be removed
and if you could put the search bar at the top right or somewhere else, that would save almost 100px. Similar for the wiki.