I know it’s thoroughly boring, OP, but unless you know someone’s tastes/preferences extremely well I think I’d go for something like John Lewis vouchers, where they can choose from so many nice things, inc. baby things, if she wants.
You’re not the only one, Bibbity - I’ve had to make it very clear to dds never to give me any such thing!
As for ‘experiences’ such as ballon rides, IMO you need to know the person’s likes very well. Dh was once given a glider flight, which he thoroughly enjoyed, but before they went up, the pilot said, ‘Do you actually want to do this, or do you just feel you have to, because it was a present?’
So presumably that happens quite a lot!