Great idea! I really like that a lot. Being Devils advocate, could it be extended to all modes though? That way there can be no argument of consistency if instancing is unkind to you.
I’m not opposed to it in principle but I don’t see how it could work without some kind of asymmetry between Open and Private modes. Reason being people “retreat into solo” because the possible presence of other players adds an additional logistical and practical overhead that they can negate by switching modes. If you equalize the NPC presence in both modes, you’re back to square one as near as I can tell.
The way I imagine the system would work is if there’s a bunch of people in a region only playing in solo, that nothing would change. But as soon as people started playing that same region in Open, the threat level of the region would start to ramp up in Solo, while remaining the same in Open. At a certain point, Solo players would start to make a risk assessment as to the benefits of “retreating into open”, where the much more sporadic and unpredictable threat of PvP might be more efficient to deal with than the guaranteed continuous pressure from an escalated NPC threat level.
There would also be a layer of meta-strategy here, too. In relatively quiet, empty, uncontested areas, players would have an incentive to work those areas in Open because it would be more efficient, and as an added benefit they would also be preemptively ramping up the threat level for the opposing side.
Anyway if you can figure out a “mode neutral” version of this mechanism which would still work, I’m sure that would be better; I just don’t have the creativity to think of anything like that, mainly because the different modes are
already inherently asymmetrical in that one is dynamic and chaotic while the other is always going to be more predictable and straightforward.
And I don’t want to get too deep down this rabbit-hole because all of it presupposes an amount of new work and a commitment to balancing and play testing from Frontier that is obviously pure fantasyland at the moment. But hey maybe they’ll take some inspiration for when they relaunch Elite in 2020 or something.