Should you under this scenario still avoid saving your encrypted private keys online?
Not under any circumstances.
If BIP38 is power intensive and bruteforce resistant with even a reasonable password (let alone one Diceware-generated) why should you be worried about scanning your private keys and uploading them to a cloud for example (that way you would have access to them whereever you might find yourself?)
The whole idea of the cold wallet is to have it disconnected from the outside world fully. It will not be called a cold storage if its exposed to the internet at any point of time.
In the event that the password generator is somehow flawed or a vulnerability is discovered in whichever client you used to generate the keys in, you will be 100% safe. I don't see much point in generating a paper wallet and then storing it online, you're better off generating a wallet and just storing a backup there.
I get what you are saying.
The problem that I have with paper wallets is the FACT THAT YOU CANNOT CARRY THEM AROUND IN YOUR HEAD.
Lets say you created your paper wallets offline, printed them offline, laminated them, put them in a waterproof/fireproof envelopes, protected them with strong password, printed them offline multiple times and stored them in a bank vault.
That would be considered pretty safe.
But the problem is that you can not carry that information in your head.
Every time you want to/need to have access to your bitcoin you would need physical access to your encrypted printed paper wallets.
Lets say:
1. you are half way accross the globe
2. the bank does not grant you access to safe
3. the goverment does not grant you access to the location where the safe is
...you are essentially safe from anyone stealing your bitcoins but you are equally unable to spend them yourself.
That is why I thought scanning the paperwallets, encrypting them with some kind of tool (not sure which one) and uploading them as an encrypted file on a cloud/clouds would be cryptographically secure but still accessible to you should you lose physical access to the places where you stored your wallets.
