I hadn't thought of that before, but I think it is a fabulous idea. I too sometimes forget to check my IPTC info before hitting the ingest button... I know, I should just stop being such a bonehead, but as that is not likely to happen, forcing the IPTC window to open before ingest would be the next best thing.
If the IPTC window pops up when you hit the Ingest button (having chosen to apply IPTC of course) that would be fine with me, but I wonder if it may create an extra step for some people who perhaps use only variables in there IPTC and therefore don't need to change IPTC info every ingest.
Perhaps the ideal solution for everyone would be a simple "Open IPTC window before Ingest" preference.