I like the Steel Idea! If you ever did go wood, could you not add a 2nd beam, across the same span, add some bearing points, and make it outta micro Lam? Or just 2) 2x12 SYP, w 1/2" ply in the middle? Anyway, Metal IS STRONG!!!!! And YOU'RE THE METAL MAN!!!!!!! Have a Blessed New Year Steve! Peace,!