I really love the guy actually! He was one of the most useless heroes prior.
You can shoehorn him into creating certain luxuries you only need a couple more to achieve monopoly. Put him on marsh and he can only generate sugar, truffles, or rice for example. On flood plains it's pretty much wheat, maize or sugar only (bad choice since you are more likely to get bonus rather than luxury resources). Desert flatland is guaranteed to give you a luxury of either silver, ivory, salt or incense (no chance for copper since it's not on a hill).
Early game it is better to put him on a woods/rainforest hill tile for the yields though. He has a miniscule change of generating a bonus resource there since there are so many luxuries that can spawn on such terrain.