I want to divide this comment into 2 parts.
The first is, as you mentioned you think it is better not to implement ranges in factions, my opinion is that you are wrong, let me explain. I think it's great that you don't want to put GMC, it is understood, but you can leave the ranges that we have because for something it is full Network, you can also add commands such as feed, heal, / enderchest, / PP / fly (in almost all current servers the highest rank has fly) / wb and also if that's okay with you, depending on the ranks you could apply a ./kit of different types, construction, combat, raid , etc ...
Second point, as you said according to you say that you want to add the building stones plugin, I ask you, how funny is the factions then if it cannot be raided? As you have said, you can implement the Vampire survival and Space factions configurations, you can see that both have the plugin of the ./f commands, they are a set of commands that among them is the / f Claim, / f Claim auto, etc. With these commands, if the explosions are left activated, you can raiders, that is the grace of factions.
Then I'll leave you a link to a pretty good factions plugin.
Link:
https://www.spigotmc.org/resources/myfactions.88061/?__cf_chl_jschl_tk__=pmd_e9vWq9Ze1XAJl4CYnAFk3pSbOUUfehG1r8g.z5HIreo-1631200456-0-gqNtZGzNAfujcnBszQx9
Conclusion: it seems to me that you want to go too fast and use the easy way of control "c" control "v", that's when mistakes are made and the mode full of bugs and problems ends
[S+][GoD][$$$][Yonkou] Cursed