upgrades?

i have a regular cab 6ft bed 99 Z71 5.3 with a granatelli mas air sensor...K&N intake..airaid tbspacer...msd wires...bosch plat 4 plugs...granatelli predator tune with firmer shifts and shift points at 1-2 40 at 5800 and 2-3 at 80 at5700 and 3-4 at 5700...flowmaster 50 series exhaust with turndowns.. anybody have any ideas on what upgrades i should do next?? im going to get a nelson tune and msd ls1 coils and bbk throttle body other than that what should i do?

Cam. I saw an enormus improvement with a cam.