There are several reasons simply making the reality bubble dynamic is problmatic. Inrough order of importance:
1. Making it a constant simplifies a crapton of code, if it were dynamc there are inumerableplaces in the code that would have to make adjustments based on the configured vaue. In the worst case,significant parts of the code would have to be rewritten to support it.
2. Providing consistent game experience on different computers is a major issue. This isn't like in minecraft where adjusting chunk distance mostly influences what the game looks like, if you can adjust the view distince you can at a minimum see and avoid enemies from further away. I'm sure there are other instances where it would make the game significantly different forpeople who can afford to increase reality bubble size a lot. We want to make everything work for all the players.
3. As girlinhat points out, the benefits of increasing bubble size increase roughly linearly, the costs increase roughly exponentially. There WILL come a point, and sooner than you think, where you hit a performance wall. IMO that performance wall is most likely far short of where we'd see transformative changes to gameplay.
Now, more sophisticated forms of dynamism, like effects continuing when off-map and being ableto interact with enemies off-map are both things we want to suport.
We have a model in place for ongoing effects being udated when they're loaded, we just need to streamline how that works a bit and apply it uniformly.
As for shooting things off-map, we need to get hordes working properly before even looking into it, but having a sniper mode where it dynamically loads submaps outside the reality bubble just while you're aiming a long ranged weapon is something I'd like to support.