I strongly advise you not to use paper wallets.
Paper wallets are fine, as long as you know what you're doing. That includes knowing that almost all websites that offer paper wallets will scam you. Even when you use them offline, they can produce a compromised private key if the source is compromised.
I have written a program in Java which creates old-school paper wallets. Therefore I am almost certain of the source code's validity. However, I believe it is much easier to use an airgapped device for signing transactions. Paper wallets are fine, as you said. I think though that nowadays, it's better to use more modern approaches. Anyway!