For me, Stun/Body is a feature not a bug. I haven't seen many other systems that model the cinematic (and pretty realistic actually) conditions of being knocked out without being fatally wounded or dying but conscious.

re: The Speed chart

I found that that easiest thing to understand about Hero System honestly. It was pretty quick and intuitive for me. There are 12 Segments in a Turn. Your Speed score determines which ones you receive an action on. Either write those down or glance at a chart. Speed and the Speed Chart have never been a stumbling block, IME. Maybe if it was renamed something like Actions or Actions Per Turn?