I'd hate the break this to everyone... but the "Server strain" is an easily addressable issue when it comes to network ability and being able to expand. The harsh truth is just that Square Enix tends to only tell half-truths when it comes to this to try to appease the backlash. Anyone who has played their MMOs since 2004ish knows this is true. They CAN do it, It's within their POWER to do it but as a company Square-Enix is behind on the times and they don't understand how important this stuff really is.

Little example is just look how long it took for them to give basic QoL improvements on their other MMOs and you'll see what I mean. QoL improvements are just as important as adding playable content. People spend more time outside of content than they do inside content on average... thing is... things like gold saucer, chocobo races, and housing all COUNT as content within the game. Which is what many people seem to fail to understand.

Instances housing would work fine. I imagine they could easily do it like they did apartments. ____ many players can have instanced housing in this area. For those who want the whole ward system they would obviously gravitate to that... those who don't care would likely opt for instanced, especially if you could upgrade housing size within an instance. Bottom line, they need to add restrictions to the system as a whole to help prevent all of this.