In the case you are referring to possibility of losing the change:

Electrum uses the sending address as the change address if you have imported a single private key. So, the remaining balance will be sent back to your paper wallet and shouldn't worry about it. (Using a same change address can damage your privacy, off course)

The main issue when you import a paper wallet into electrum is that, your private key touches the internet and the paper wallet is no longer safe to use. The solution to this problem is signing the transaction offline and use an online computer only for broadcasting the transaction.