I think "permanent consequences" is a valid design decision, just like permadeath. And it's much better than being able to save only on checkpoints. So if your game is genuinely designed around that mechanic, I'd say go for it. If anything, you may consider an optional easy mode with unlimited saves.
Also it'd be of course good if you provided one save per playthrough rather than just 1 save forever.
Also it'd be of course good if you provided one save per playthrough rather than just 1 save forever.