My blue wallet setup

Hey everyone, so far I'm using the following wallet setup and I'm interested in your thoughts:

A 3/5 multi-sig created in the blue wallet iOS App. After key generation I stored all 5 keys in different locations (some are completely air gapped, some are online devices). On my phone only one key is left, the other four were "forgotten" by the blue wallet app.

To sign a transaction I would import two more keys, then execute the transaction and then forget the keys again.

I'm thinking that this is a great method, because there is no single point of failure (while I'm not transacting) like in a single cold wallet and its completely free.

On the other hand I am trusting blue wallet with the entropy generation (even though source is on github) and need to import keys to my online phone every time I want to transact.

If I switch to a single hardware wallet like a coldcard I actually feel less secure, since my seedphrase paper is a single point of failure.

What are your thoughts? How safe is this setup? Is there a way to have a multi-sig setup with a hardware wallet?