That's a good way to do it, I don't have a blockchain wallet though. However, it would be better if it can be done through an script by myself. I was looking for such a way. I guess we have such option to do that.
You don't need to create a new Blockchain wallet.
I would not trust them with my money.
I've used it for a certain address from one of my HD wallets. No private key sent to Blockchain.