With my first baby, I used to aim for one main activity out of the house each weekday. It might be a big shop at the supermarket, a trip to the shopping centre, rhymetime at the local library, a walk or playground trip (either just me and the baby or with a friend and her baby), a mummy-and-baby class, Baby Swimming class or a free swim at the Family Sesson of our local pool, or NCT coffee meet-up, a drive over to see the grandparents (or invite them to us for the day).
The rest of the day would be taken up with housework and meal preparation, playing/music/reading/playing in the garden etc with the baby, bedtime routine, sleep training and naps.
At weekends, my husband didnt work so he would often help more with my DD and free me up to have time for a bit of self-care or to let me pop to the shops on my own. We would see PILs a few Saturdays a month (they were about 45 mins drive from us. We would usually try to eat out sometimes, and sometimes meet friends for a pub lunch.
We might also have a few big day trips out but that tended to be when DD was older and could appreciate it more without collapsing into tears of exhaustion or needing an ill-timed nap.
As a first time mum I think I was a bit unsure of myself, and i really hates disrupting my daughter's nap cycle and bedtime too much. Like most parents, second time around routines become less fixed and my second baby would sometimes have 6 separate trips out of the house (schools runs and after school clubs for older DD along with normal requirements like grocery shopping and visiting PIL and my mum).
I recommend having some "fixed" commitments but not too many - leave gaps to be spontaneous! Definitely do "something" each day if you possibly can, it is great for stimulating and wearing your baby out and getting a good night's sleep!