You don't need low level versions of units like Deadra and Felmer in a no level-scaling mod. Players should just be slaughtered by them.
You're right. My post wandered off-topic and addressed problems beyond strictly level scaling. The way I see it, there are two ways that it could be accomplished. First, it could use a Morrowind style system where certain enemy types are fairly fixed in their power level. Draugr are always weak starter enemies and dragons are always godlike engines of destruction. The problem with this implementation is that the low enemy diversity would mean that there would be only a handfull of enemies to fight at any given level. In Skyrim, a starting player would only fight generic cloned bandits. Morrowind was able to pull of this type of system because it had many enemies for each level of play, such as named humanoids and diverse wildlife for beginners.
The second possible system would be keeping the system of Draugr, Draugr +1, Draugr +2 that Skyrim has now and making it so that some dungeons will always be filled with Draugr +2. The problem with this is that it keeps Skyrim's treadmill, and there's no real way to tell these apart. In Morrowind, you could tell by the types of enemies or by the architecture when you were completely out of your league.
Although I will admit that this is just my opinion, I don't think that there can be a satisfying solution to Skyrim's level scaling without the introduction of new enemies.