Nick, I do have amchoor. I think I'll try pairing it with some tamarind AFTER the holidays! In the meantime, I tried another batch with the following alterations: increasing the lime juice by 60% (including the pulp), adding 1.5 tsp. of fish sauce, omitting the cayenne, and adding 3 T of toasted, chopped unsweetened coconut. The result was surprisingly similar to the first batch in terms of tartness/tang (rats!) and saltiness. Of course, it was less hot/spicy (better for my recipient audience). The coconut was a good addition.