The trader evaluates each trade and assigns 0 - 3 stars. 2 stars means that the goods wanted have the same value as the goods offered - a "fair trade". 1 or 0 stars indicate an expensive/very expensive offer and 3 stars indicate a bargain. The vast majority of players as well as the game developers agree that goods of the same tier have the same value. In this case the star rating makes sense and allows for a quick overview. In case of cross tier trades, things are not so easy. Most players will agree on a value ratio of tier 1 : tier 2 : tier 3 of about 1 : 2 : 4. The developers go for 1 : 4 : 16, and some players advocating for 1 : 1 : 1 - some even think that tier 3 is less valuable than tier 1 and 2. There is no agreement about a correct ratio. It is different for every player. Given this fact, the star rating will be wrong for almost everybody. My suggestion is to keep the star rating for same tier trades, but to drop it for cross tier ones. Cross tier trades should always have 0 stars, with an explanation popup saying that the trades incorporate different tiers of goods, and that therefore no adequate trading ratio can be determined. This will have an impact on the sorting of the trades - the cross tier trades will appear among the genuine zero star rip off trades. I do not believe that this will have much of an impact since most players do not accept either outside the fellowship.