First, thanks to all for the responses. I think I understand now. It's just frustrating when you warp into one of these and it's target-rich, then seconds later it's cleared out and you ain't got jack. I have fun with them. I do they all the time and I'm on my fifth captain. It's a way to get quick, single-player action…
Thanks all. I'll play around with keybinds. I was using tab, and it barely works. Yeah, a Target Next Closest Enemy seems like a very basic function for space combat. Surprised it got left out.