POC and filter options should include *overall* Delta

Currently, when setting up highlighting for POC (maximum level) and filters, it is only possible to choose between positive/negative delta or bid/ask. There should be an option to use overall delta for both of these tools. To highlight this problem even further, if you try to use "heatmap by delta" in the cluster options, the entire functionality is broken as it only shows you positive delta clusters. The software needs to have the ability to look at the overall strength of delta (whether positive or negative) rather than having to choose between one or the other.