A bit late to this, but I will try it with capital on marble. Wet corn allows you to grow to size 3 on turn 22, work the gold, and once the plains hill mine is online, pump settlers in 6 turns with IMP at size 3. For me at least this is too good to pass up. The coastal site in comparison forces you to choose between extra production and gold. With capital on marble there is already a way to set up city 2 with fish, a few forests to chop, and a mine to work, and further exploration could reveal an even better city 2 for GLH.