Good for you! 😎 Here are some points you might still want to consider:
➤ Flexibility: You can do far more with a Frankenwallet than with the stake pool or key management tools on a hardware wallet.
We should assume the UI for hardware wallets will be state-of-the art, but some including myself will never be satisfied without a full scale, functional computer screen in the air-gapped environment… which for the Frankenwallet includes the ability to: access the host machine files, create and edit secure text documents and spreadsheets, prepare email and other communications (to save on the host, not send!), package our your will & testament with the encrypted keys & seed phrases in it, etc... only your imagination is the limit.
➤ Privacy: Nobody ever needs to know that you have a Frankenwallet.
As the world governments, regulators, tax authorities and criminals increase their efforts to identify cryptocurrency holders, there is a threat of security breach via the purchase or warranty records for the premium hardware wallets, which naturally require owner authentication and support. Please see and consider: Ledger users threaten legal action after hacker dumps personal data (2020-12-20)
➤ Autonomy: You might trust the company making the "black box" but can you trust the world itself?
Security conscious people will know that neither closed nor open platforms are perfect. Yet there is a long standing argument supporting open source tools: that code visible to the public will quickly weed out any additions that provide "back doors" through all but unanticipated and accidental exploits. Hardware wallet users should ask themselves if they can have that same level of trust in a device manufactured in secret: especially in this modern era when covert surveillance through electronic devices, often government-mandated, has become the rule rather than the exception.