I happily recommend Irma's place, when you need a safe and quiet accommodation near city center in Stockholm. I stayed for 2 weeks and have no complaints.
The room is a cosy and private room behind the kitchen. The bed is comfortable. Breakfast is included and there is a possibility to do laundry. Metro is a 5 minute walk away and it takes 10 minutes to city. It's also a nice walk to city.
Irma herself is lovely! Always ready for a chat but lets you have your privacy.
There's no reason why Irma's place wouldn't be an option for you.