I imported my keys into Electrum from private keys. So the wallet has no seedphrase.
So of course I have the private keys, encrypted in cold storage. I guess I have a preference for having the private keys - in that they are are the literal key as opposed to a seedphrase. And that made me feel more comfortable when multibit went the way of the dinosaurs. And if Electrum does too and I have the keys I can't be cutoff from by bitcoin. Hence the question about change addresses - because even if I setup a new wallet I have to move bitcoin out to it. And I have this fear of losing some of it as my wallet isn't a typical wallet.
That's why I wanted to know how Electrum functioned for that use case - private key import - given that in my eyes at least it's the only platform independent way to hold bitcoin.
This is why seed phrase was created.
Also keep in mind that your concerns would have been valid for a closed source wallet not for something that is 100% open source and is as popular as Electrum. We already know all the details of how each private key is created from that seed phrase so even if Electrum wasn't being developed in the future we can reproduce it easily.