I don't think I can trust any platform with anything I consider 'Secret'.
Checked the Github but really didn't get much and I think i would wait for those that have opened the Sylui code introduction.

If am not mistaken you are using mnemonic phrase as the private key?
The method you implementing is it in alignment with BIP 39, or is the randomness arbitrary.
Well I think it's and personally I don't know if the randomness is random enough and this could be considered 'unsafe'

The standard for seedphrase is BIP 39 and this doesn't follow such and what that uses BIP 39 wouldn't recognize this
Except the aim is keeping the private key in another form which I think is unnecessary.