After 2 years, you should stop with "if Miller can stay healthy". You better be planning on him NOT being healthy. And I don't think you can rely on 30 year old Kamara to be healthy all year, either. Then who are you left relying on? Mimms? That's a loss waiting to happen.
Miller can't even line up right when he's healthy. Pass protection lacking, drops passes, doesn't get the playbook, and always injured. It actually makes sense why he was in Allen's doghouse.