Thanks for all of the replies... I agree that the vendor is being reasonable and that I do not want to press my luck. Having said that, it seems like people on the forum recommend shooting for a potentially better diamond. Because this is the case, I wrote a sensitive note to the vendor to ask if there might be any other candidates for the swap. Specifically, here is what I said:
"Thanks for sending the certifications, I appreciate you selecting a few diamonds to choose from. I have had a chance to look at the diamonds via the certifications and I think we are close! I really like the 1.55 (G, SI1). In addition, I liked the 1.52 diamond (G, SI1). The only concerns I have with the 1.55 carat diamond are that the crown angle is a bit low and the pavillion angle is a bit high. This is what makes the 1.52 carat diamond appealing - however, the concern I have with this diamond is the lack of a 3X cut. Having said that, I was wondering if you might have any options that combine the characteristics of the two? Thanks for your consideration!"
I feel like if the vendor doesn't want to select more diamonds, he can say so and I can choose between the two mentioned here (they are cert 2 and 3, btw). If these are the three diamonds from which I must select, I will do so and I will be more than happy about the exchange. Still, based on the feedback I received today, I wanted to at least ask about other diamonds. In regards to my reading of the interaction so far, I don't think asking about other diamonds in the manner described above oversteps the boundaries of our relationship. Then again, I could be wrong. I'll keep you posted.
"Thanks for sending the certifications, I appreciate you selecting a few diamonds to choose from. I have had a chance to look at the diamonds via the certifications and I think we are close! I really like the 1.55 (G, SI1). In addition, I liked the 1.52 diamond (G, SI1). The only concerns I have with the 1.55 carat diamond are that the crown angle is a bit low and the pavillion angle is a bit high. This is what makes the 1.52 carat diamond appealing - however, the concern I have with this diamond is the lack of a 3X cut. Having said that, I was wondering if you might have any options that combine the characteristics of the two? Thanks for your consideration!"
I feel like if the vendor doesn't want to select more diamonds, he can say so and I can choose between the two mentioned here (they are cert 2 and 3, btw). If these are the three diamonds from which I must select, I will do so and I will be more than happy about the exchange. Still, based on the feedback I received today, I wanted to at least ask about other diamonds. In regards to my reading of the interaction so far, I don't think asking about other diamonds in the manner described above oversteps the boundaries of our relationship. Then again, I could be wrong. I'll keep you posted.