Hody, www.walfisch-freiburg.de takes 2-3 seconds to load. Your other site, tribe-online.de comes up partially in a couple of seconds but took about 10-15 seconds to load completely, with the graphic in the right sidebar.
One thing I would do is to go to ATO/Configure CSS and JS (at the very bottom) and make both files External, so "Yes" to both. It may help load fractionally faster, but it also cleans up your code. I tried to look at your graphics to see if they were optimized properly, which could be another reason for the slow load, but you have some javascript or something that prevents me from looking at them
If your graphic is, for instance, 250px x 150px, make sure your original graphic is that size, too. Do not use a 500px x 300px graphic and scale it down to something smaller.
As for the look of the tribe-online.de, yes it does look rather "Industrial," however, I am not your demographic and besides, it is a matter of personal taste. Why don't you ask your customers/viewers if they like it?
[note: making the CSS and JS external will not save any time for the first page load and will actually add a fraction of load time because a nother reqest is sent to the server. It will save time in viewing other pages since the CSS and JS will be in memory and each page will be smaller when loaded - JD]