Sync imo is one of the best cloud service to backup sensitive data. You can always encrypt data, then store it on Sync. Stuff like your keys and anything else. Free account is limited in space but its sufficient for most purposes. It's a very secure cloud service. Also, make a backup on a pendrive or a harddrive and don't use it regularly. Also can keep a printed copy of your keys. :)

Anyways, good to see you back. Cheers