In my opinion, the Castle is the most "average" town. It has neither significant advantages nor significant disadvantages. The absence of a fifth-level mage guild and special buildings (artifact merchant, treasure trove, mana vortex) is unlikely to please anyone. Things are slightly better with warriors; I consider crusaders, champions, and archangels to be the most useful. The Castle lacks a specific specialization (Swamp - defense, Stronghold - attack, Tower - magic). Prices are also average (except for angels/archangels).