You can wipe the master key when you suspend. However it will just mean that there needs to be some unencrypted storage to write down things like incoming text

You can wipe the master key when you suspend. However it will just mean that there needs to be some unencrypted storage to write down things like incoming text messages. Caller ID will also not work (or be stored in the unencrypted storage). There are ways to do it, but you will lose security/convenience. It all depend on your threat model and how inconvenient you're willing to make your phone.