If we want everything (including creating BTC transactions), we somehow need to create them without the users direct intervention. Storing some private keys in the NXT blockchain is not an option.
Yes, agreed, I would say make it fully automatic
That would be the most convenient option, I know. But how to create a blank transaction without the private key of the user AND without revealing the secret necessary to perform the corresponding transaction on the other blockchain.
We have time to discuss this until AT and AE are up and running.
Yeah, that's the 3Mil Nxt question right there.