We’d want more than just one trade. A single price point says very little. Two people might agree to buy and sell 1 NBT for 2$ or 0.50$ for whatever reason. That alone is not a problem. The orderbook contains much more information. If someone trades 10$ worth, that is not the market. Deviations of prices for tiny volumes should not be the focus.
I’ve already built the streaming service and data store. Should be available in a couple of weeks. The more accurate price is the (bid+ask)/2, and for all exchanges. But even then one is only looking at the top of the book, and there is no measure of quantity.