The castle of your dreams.

Probably, following the same principle as the Conflux was created, it would be reasonable to create some kind of Thief's Castle or Den for other "homeless" factions – Hobbits, Pigs, Thieves, Trolls, Bedouins. You could also add Snipers and Rusty Dragons (they fit the theme, even if not in terms of strength). Peasants, Mummies, and Wizards are not needed. Magic level 3 would be sufficient. Just adjust the monster parameters for balance, and they already have dwellings. There's no need to reinvent the wheel, and it would help the "homeless" factions. Creating something entirely new might spoil the classic feel. I'm not a fan of WoG.