The way I see it, I would keep the tallest tower in a overflow corner and lay other one pointing the opposite corner. Or take it a part and do a gradual decrease slope from the tall tower towards the opposite corner. 
Or even better would do two decreasing slopes with an open lagoon/pass(pointing opposite corner to the overflow) running between them, where your tower by the overflow being the highest point. 
		
	
		
		
		
		
		
	
		
		
	
	
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