If you are very committed to the standard of self-custody of sats and feel that ecash sats do not meet this standard, how about maintaining a balance of only 100 ecash sats? 

When the balance exceeds 100 sats, you can melt them back into Lightning Network sats. If the balance falls below 100 sats, you can mint some ecash sats from Lightning Network sats.

This is why we added mint and melt operations here. nostr:note1spv99eg2l4y4k59qghx8gqlq3hrtuze552n2s67jj9v84y0u8znqfyf0sp