Old chestnut this one. FR would have a big (probably too big) an issue, but then they specified a downgraded (economic) engine spec. Others, well what routes would the want to operate with how much fuel? Many a 737 has landed and taken off from SEN, would a modern 737-800 be able to work the runway? With every seat occupied? I think the real question is would any operator be enthusiastic about joining easyJet in running any route that limited the amount the of seats that could be sold to less than 100%?