Things I've enjoyed so far:
Batch cooking - things like bolognese and burgers, beef or chicken pies and pizza dough and sauce (which can be pizza or pasta sauce) I've also been able to make me and DH really nice wholesome dinners each day which I've enjoyed.
Crafts - I'm crocheting a granny square blanket for the baby, I can do 1-5 squares a day whilst watching an episode of something on netflix. Also I started a cross stitch which I do whilst listening to a true crime podcast usually. (Side note: Podcasts have been great!)
Dog walking - I take my dog on a 30 - 90 min walk every day, I feel better after getting some air even if its rainy and I like to think its probably good for helping the baby get nice n low. Don't go too hard though, I walk dead slow.
Baths - Seriously! I've taken a bath nearly every day, I use bath bombs and bubbles and light candles and put music on or read or listen to a podcast and make it last a good hour. Its lovely.
Cleaning / Sorting the house - I've redone our whole bathroom since I've been on maternity leave, just doing a little bit each day, like painting the radiator one day then the skirting board the next etc. Again, you have to be careful not to go too hard. Also I've been going through my clothes and donating to charity and also tidying those 'bits' drawers you have full of crap and odds and ends.
Ebay stuff - This one has been great for getting some extra pennies in before baby comes, its surprising how much you can get for the things you have cluttering up your loft / under your bed.
I hope this helps a little bit!