I personally dislike hardware wallets because I believe that in order to use bitcoin, you should not "pay" anything (ie. purchase a wallet device) but I can see their appeal.

This is why I personally believe that the best way is to use paper wallets.
I don't know what you mean by "weak support" but the other two are not cons.

Secure wallets that are 100% open source and reviewed are not hard to come by. You can use bitcoin core! Or better yet you can use a deterministic wallet that uses mnemonic algorithms, like Electrum to generate a seed phrase and as many private keys as you like.

Seeing the private keys is not a con. Remember this is your money that you are giving away (not selling) for it to be categorized as con. In fact you should keep a backup of that mnemonic (the keys you gave away) for the future. In case they lost the paper wallet so that those coins are not lost forever.

Finally use a cool design for the paper wallet you want to print that has holiday themes and a short guide/info about Bitcoin on the back including how to spend coins. It could be steps to use Electrum which is a user friendly wallet.
And they have to learn how to use bitcoin anyway if they want to use bitcoin! otherwise what's the point of giving away bitcoin?