I store my bitcoin at web based storage. I think web based storage is more efficient than cold storage. Blockchain and coinbase are good web based storage because of its simplicity and security. I tried cold storage in the past, but I lost my bitcoin after got a new notebook and I forgot to backup the key. So to prevent that thing happen again, I use blockchain.
Block chain storage is a nice idea to save our bitcoins there. if there is big amount of bitcoins to store then we can use it in investment so that we can get some extra amount of it. or else do mining. and wait for the price increase too.