I am not from UP but i explored it a lot, some of the best cultural things can be observed here.
like varanasi ghats, streets of varanasi, sarnath, sangam area in allahabad, and ayodhya.
Varanasi itself will amaze you. Try Ganga Aarti, Ramnagar Fort, Sarnath, Vishwanath Temple, BHU Campus along with New Vishwanath Temple, Durga Mandir at Durgakund, Sankatmochan, Siddhnath Ki Dari, Lakhaniya Dari.
Beside Varanasi Lucknow will also provide you several good shots.