There was a videogame cafe I found on the other day. At that cafe, people gather and play video games together, such as Monster Hunter series. If you are a video gamer, might be a fun place to interact with local geeks :D
I went to the Animate building before and found lots of figures. It was just fun to look at them! All of them are neat and extremely creative.
There is a famous Tonkatsu restaurant called Marugo. I find the place is very delicious. Might be good to put on your list if you like juicy pork!
My recommendation are:
1. Shopping (Electronics and Anime/Manga/Game items)
2. Maid cafe (Other uniq cafe. ex Vampire cafe)
If you want to get lunch or dinner, I recommend to go Ueno or Kanda area near by Akihabara.
If you like sub cultures of Japan, Akihabara is good.
But you are not, there are some shrines, zoo, parks, museums in Ueno.