YABU. I have two kittens (they're about eight months now) and you cannot teach them not to scratch - don't kid yourself with that one.
They're indoor cats because we live in a third-floor flat on a busy road, so we don't have to deal with dead birds or whatever, and they do happily kill any flies and spiders that find their way inside, which is a bonus! They also came litter-trained and apart from one accident on their first night here, they've always found the litter tray.
BUT I would never get a pet without DP being on board. He loves the kitties and they really are adorable, but they do scratch everything, they leave fur all over your clothes, bedding and carpets and as they grow, they CLIMB.
Mine get up on the fridge, the work surfaces, into the drawers which they've learned how to open, the bath, the sink, the top of cupboards...everywhere. They climb up the curtains and get everywhere. With a baby, you'd really need to be on top of keeping everything clean, probably shutting them out of the kitchen if possible, making sure litter tray is not within baby's reach or access etc. It's a lot of work with a newborn and if your DP isn't on board, kitty will be looking for it's third home.