The Peruvian pisco sour cocktail is among my favorite aperitifs - you won't find it better than here. A lot of people know this bar which has been around for many years, what they don't know is that the dinning is actually really good. Blinis & caviar with some bubbles are the perfect way to continue after the aperitif :)
Moma is worth a visit, but for a more lively Art experience ánd for free, one should visit Chelsea. A colony of 400 Art Galleries, showing the best in contemporary art. Running straight through is the high line, a 1 mile long linear park, build on a former railroad-spur, worth the walk.
The Brooklyn Flea is another treasure trove of odd finds, cool artifacts, and handmade goodness. If you're looking for inspiration or just something cool to hang on your wall, you can probably find something here. And if all that treasure hunting leaves you hungry, you are in luck--there's a delicious assortment of local food vendors and artisans there too.