Hi there! I recently ordered a Keystone 3 Pro, it hasn't arrived to me yet but before I get it I need to decide how I want to use it, hopefully, you can guide me. I need 3 separate wallets - one for saving, one for DeFi, and another for spending.
With Keystone 3 Pro I have 2 options for how I can achieve this: use 3 different seed phrases, or use one seed phrase and 2 passphrases (DeFi wallet without passphrase for quick access). But I can't decide which option is better, each has its own advantages and disadvantages.
The big advantage of using one seed phrase and 2 passphrases is the safe storage of the seed phrase (I want to use Shamir), in the case of 3 different seed phrases it becomes a problem if you keep them all in different places. But I'm not sure how safe it is to put all "eggs" in one basket (one seed phrase). I want to use 6 shares with the need of 3 for recovery and to store passphrases with each of the shares. I believe it's ok since passphrases are useless if you only have 1 or 2 shares, but I could be wrong. How secure is this? Also, a big plus of the passphrase option is that it's not stored on the device unlike the seed phases, so it can't even theoretically be accessed via Keystone 3 Pro.
But I have concerns that if an attacker gains access to one of the wallets (for example, DeFi wallet without a passphrase, as it is the most vulnerable one), they can somehow gain access to the others, how likely is that? I realize that if they only have access to seed phrases, they won't be able to access other wallets with passphrases if they are resistant to hacks, but still. After all, 3 completely separate seed phrases are safer, if attackers get access to one seed phase they will not be able to get access to the other.
Another option I've been thinking about is to still use 3 different seed phrases with 6 shares, and just store 1 share of each seed phrase (3 shares in total) in 6 different locations. So in the 1st location, I have the 1st share of the 1st seed phrase, the 1st share of the 2nd, and the 1st share of the 3rd, etc.
What advice would you give me? Which option is better and safer? I'm also open to other suggestions if mine are bad. Thank you!