As per the question is coinbase a safer wallet than blockchain
1.Coinbase is not a wallet.Coinbase is an exchange.
2.Coinbase doesn't give your control your wallet,blockchain.info does.
3.Being said that,blockchain.info runs online which makes them vulnerable to n number of attacks.Alternative : Electrum.
1.Coinbase has been considered as a third party wallet. You have to admit this truth. Sorry
2. You can not fully control your Bitcoin in blockchain. They only let you to control your private keys and some other alternative things on it
3. All online wallets can be harmed by hackers or some DDOS attack.