I had a funny feeling that I'd be wrong. 15 posts between you and larkin should outwit my 15 minutes analysis of a picture and spreadsheet.
Great Lighthouse... hmm... DocTs claims to have built the MoM on a standard sid island map. It is probably worth committing a city to, but I find that building wonders on sid (except GL, because the AI skips lit) usually takes a whole civ dedicated to building it- improving that city's tiles first, joining workers, raising lux instead of hiring specialists in that city, etc. I'm not sure if it's worth that, since our chances of hitting it are slim. But it would be huge. I always find that the AI that builds the GLH on island maps pulls ahead because they get contacts the quickest, especially if there are few seafaring civs.
Great Lighthouse... hmm... DocTs claims to have built the MoM on a standard sid island map. It is probably worth committing a city to, but I find that building wonders on sid (except GL, because the AI skips lit) usually takes a whole civ dedicated to building it- improving that city's tiles first, joining workers, raising lux instead of hiring specialists in that city, etc. I'm not sure if it's worth that, since our chances of hitting it are slim. But it would be huge. I always find that the AI that builds the GLH on island maps pulls ahead because they get contacts the quickest, especially if there are few seafaring civs.