Since you are just for a day, and important site you already included. Include morning aart at Assi ghat and just beside it, there is a Tulshi Akharda and Tulsi temple (where still real Ramcharit manas is preserved. You can check my youtube video in name of Ghats of Varanasi (https://youtu.be/c3M-ATV5tsg) where I had shown the location. Happy travelling
Go to Chandra Prabha national park. It is merely 60kms from Varanasi and includes beautiful flora and fauna, waterfalls and wild animals ofcourse. U can try different foods on godaulia if you're a foody. Zostel is a great place to stay in Varanasi. Rest you've covered the main two spots. I am afraid on the context of venue Ghats are the crown jewel of Varanasi.