Is 5-6 Days Enough?

I am planning a solo trip to Tokyo in May, preferably after Golden Week from my research for more affordability and fewer crowds. I am a female, middle aged, so I’m not looking for too much nightlife. Mainly, I want to site see, visit museums, eat good food, people watch. I am looking for a mid-range hotel. Not sure if planning for 5-6 days (excluding my travel days) is enough. Am I cutting myself too short?

Also, any hotel recommendations for $120-150 per night?