Ok, I have condensed the overly long sitenotice and edited the landing pages it directs to. Then i have moved the huge language box to the bottom of the page. Those are quick fixes, which may need some finetuning (or reverts? ;-) )
Over all I do not think that we have a major problem with our mainpage. It just needs a more regular clean up. We should not forget to expire the donation notices Crystal guy / Tropenmuseum after reasonable time.