Stay at home moms, how much do you play with baby or let them play alone?

To start off with it's not like I totally ignore my baby. When she is eating at every solid meal I sit and talk and sing with her. So thats morning, snack at lunch, and dinner time. And I read her a book once a day, and one at bedtime. Most of the rest of the time though she is independently playing, right now she likes to walk along furniture or just crawl around and shake toys. And it's not like I'm just sitting and watching TV while she plays, I'm cleaning and getting things done while she does her thing. And of course if she gets upset I go to her. But I have been wondering if I should take a little while to get down and actively play with her? She is hitting all of her development milestones no problem in fact she does really well with everything. I don't know what do you guys think?