All public addresses generated from one of the accounts in your wallet can still receive funds, even if they no longer appear under Request. As explained here, a new address will automatically display under Request once the previously displayed address receives a payment.
In Settings -> Addresses, you can click on Manage Addresses to the right of each account to view all of the labeled addresses that have been generated for that specific account. Clicking Used Addresses allows you to see every receiving addressed ever generated within the account, as well as the current balance of each of these used addresses. Please note that when you send bitcoin, your Blockchain wallet automatically selects addresses to spend from. That's why the current balance of an address can be different from the total received value.