you could make class system like this
  Mayor: can buy land cheaper( towny plugin) and get more money from taxes 
 Builder: he can place some things others cant place and he gets a chance for bonus drops 
 Trader: free shops at main district and some more bonuses like 1% more money etc... 
 wizard: The only one able to make enchants and potions. 
 Architect:limited use of worldedit able to destroy blocks with 1 click 
 Priest:able to make potions and heal players a limited times per day 
 and you can make levels for each class for example at level 1 wizard will be able only to enchant.. lvl 2 potions etc... 
 towny plugin is a way to make towns and buy land without the help of mods 
 it is cool cause you can have taxes and other cool staff <object class="emojione" data="
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