If you want to cut out all the reading, skip to the last paragraph that is underlined. It should cover the basics, but I do recommend reading it all (it's a pain I know).
My only problem with this while suggestion is that if you were to implement this, it would kinda force the players to adapt a building style they may not like or even suit them at all (could even be game breaking to some players). As it is, different building require certain blocks to be within a certain radius of the region chest. There is no way to stop a player gathering all the blocks needed for that region and compacting them into a cube to just gain the regents/ benifits of that region. It's down to how the person creating the region wants It to be made.
Some may see this as a huge design flaw within how the system operates as it could lead to some "ugly" towns/ buildings but on the other hand. It could form huge power houses of towns creating a ridiculous amount of materials but why not allow players to do this? Talking openly, there are two types of players. The creative player and the player who just wants action. Normally, the creative guys/ gals will take a lot more pride within how their build looks while the action people want to burn those creations down and spent their time pvping or killing mobs rather than building.
The creative players (I'd like to think I am one too) will create these beautiful vast villages. Other than looking good, it has a bit of functionality giving the residents materials as well as protection (to an extent). But, this is where the catch comes in. Do you as the creative player go for pure aesthetics above ground or do you build an underground city that has natural protection as well as a lot of functionality, then build a aesthetically pleasing city above ground (for show).
From my past experience using hero stronghold, looks doesn't save your ass when the raiders come knocking (arrow turrets do). The first town I created was an underground city based within 3 or 4 decent sized ravines. I must of spent a good 2 weeks setting it all up until I grasped how to set up sub-regions. More specifically, miner sub regions. These came in the form of coal mines, iron mines ect. So, after having a mess with the regions, my new found town has now got functionality producing me a reasonable amount of resources as I carried on building (I was going for a very tight, dwarf feel with little paths everywhere but the sub regions did change my build style slightly).
However, me still being a newb didn't think about town defences as well as actually having a functional layout (honestly my town was like an underground favela with sub regions and houses everywhere, amazing to get lost in). So, shorty after I started feeling comfy and proud of my build, raiders came knocking. To cut the sob story short, every sub region was pivilaged and my town ended up becoming a crater.
This hit me hard as I did invest a lot of time as well as resources in setting up the functional side of my town as well as my aesthetically pleasing side (I only got raided because someone took advantage of a bug with wards at the time
). This is where I made my mistake. I tried to combine both aesthetically pleasing as well as functionality within the same builds (as well as not setting up any defences at all).
All in all, players will still continue to have very different opinions on how certain things should playout. I am very biased to the aesthetically pleasing side but no matter what. You should not force players to the point where they have to produce a "nice" looking town to gain the benifits of hero stronghold as well as develop as a town. Not everyone has the time nor skill to build nice looking builds. Enforcing such a rule would negatively impact the player base.