In fact, I would even go so far as to say that if you are going to merely "enforce" the Born rule without justification, then you are no longer proposing an Everettian interpretation. The whole point of these interpretations is that simply "unitary quantum mechanics" describes the whole universe.
Everett himself however seems to basically "enforce" the Born rule without justification so I guess that would be Everettian.
See https://www-tc.pbs.org/wgbh/nova/manyworlds/pdf/dissertation... page 34
>we define a square-amplitude distribution, Pi...
Probability is a funny thing to deal with. Say you have an experiment where you push a button and a red light or green comes on based on some quantum effect but the green light is 1000x more likely. In many worlds you'd end up with different worlds with an observer seeing one or another but it's tricky to see how the 1000x thing comes in.