How about all of the rough/fairway/bunkers/tees/water that are not in relationships. Except, none of these should actually be in multipolygon relationships (refer to my previous comment as to why).

The fairways that share nodes all the way around greens (even the ones mistakenly tagged as tees) are another problem. These get rendered as duplicate nodes in all of the apps that use OSM as source data.

Your work. Accuracy. If you want to be accurate, these nodes/splines need to be aligned with the most recent official elevation data, not whatever old sat image OSM is able to freely use. I've seen many splines be off by 20 yds or more. 
