As far as lenses go here is what I use:  Canon TS-E 24mm f3.5L Tilt Shift,  Canon 17-40 f4L,  Canon 24-70 f2.8L, and a Canon 70-200 f2.8L.  Yes, all L lenses and all fixed aperture.  Why you would want a variable aperture I do not know.  One note here, make sure you only buy lenses with an imaging circle made for full frame sensors,  because of the lens multiple factor.  You will probably own a full frame sooner or later as costs have already come down considerably. Then you won’t have to replace lenses too.