You've got some really nice pieces there...Maybe try clumping it all together, bigger pieces on the bottom and then bridge them with the flat rocks and add the smaller ones either on top or on sides or in between. Take yourself pics of each configuration and decide what you like the best. If this is what you like (what you've got pictured) then go with it. Once you fill it with fish and corals, who knows...you may have a master piece
