Kw is a great art institute situated at the backyard of a very eastern part of town, place for many other small galleries. Auguststrasse is worth the walk and Kw is worth the stop.
Osteria Sippi is an incredible simple italian restaurant where everyone feels immediately at home. They not only know their food game but have also an impressive range of really good wines.
One of the most beautiful pieces of Berlin actually is a piece of another city (Al-Hillah, Iraq). Normally Berliners are laid back and like to hang around, drink beer and chat till sunrise. Sometimes they do get excited though, and then they start taking old war-battered stones and piecing them together to (re)form walls. The results are great as can be seen all over Berlin, but the Ishtar gate in the Pergamon museum is where they’ve really outdone themselves.