an example of what would constitute a good lighting kit for the serious photographer would include:
2 300-800ws strobes +/- a third strobe
1 med softbox
1 sm softbox
1 ea reflector - gold, sliver, black, white, diffused
2 large diffuser panels (could be homemade)
1 spare flash tube
2 spare modelling lights
5 stands, 2 heavy duty (strobes), 3 light weight (reflectors, etc)
2 arms or reflector holders
1 pack Rosco Black Cinefoil
1 set Color correction gels
1 set Colored effect gels (red, blue, orange, green, yellow, etc)
Misc grip (gaffers tape, clamps, etc)
optional extras:
1 egg crate for the med softbox
1 set of grids (10,20,30 and 40 degree)
1 wireless TX, 2 wireless RX - for wireless sync but not needed for wireless control