I'm not sure that it needs to be even that detailed. If I go sailing in the Far East I am likely to be attacked by pirates just because I'm there and they are pirates. They didn't make that decision based on any thing else. I'm a target and fair game as far as they are concerned. Now I also know this so I would go prepared and respond accordingly. That's probably all that is required. Location.
Indeed, for the first iteration of this change then yes, location location location

They would have to ensure that rewards scaled with location too though, or else there would be no incentive to go anywhere dangerous.
Take an Elite transport mission? You bet it will send you some place dangerous.
Take an Elite assassination mission? You bet it will send you some place dangerous
And so on

In the end though this should be dynamic and tied to the BGS. I mean at the moment I go into a system in a war state, and I only really know it is in war if I look at the status or see a war zone somewhere. Other than that it has precious little effect on my experience.
Edit: To be honest it is shocking that this isn't implemented already. I don't think any successful game scales opponents based on your rank? Imagine if Fallout 4 did it, suddenly the whole place would be crawling with high level opponents just because you have levelled up.