In order to decide which alternate solution would be best suited for the project, I created a design matrix. The solution with the highest total number was the best solution.
In the end, with 18 points, Alternate Solution 2 seemed to be the best choice overall.
In order to settle on a material for the piers, I created a second design matrix. The solution with the highest total number was the best solution.
In the end, with 13 points, Trex Deck was the best choice overall.