Upload & Sell: On
I'll suggest the TT Retrospective 7, or one of the Lowepro bags that Lars mentioned. I switch between my trusty old Domke F2; when carrying lots of gear, or the Retro7 when a smaller kit is in order.
Normally a 'day' kit consists of a gripped 40D or 7D, 17-40L, 100L IS and 70-200 f4L IS, a 580 EXII flash as well; when needed; with a 50 f1.4 stuffed in a jacket pocket. This bag has a zippered pocket for a 7inch tablet or iPad, and you can add a pouch to each end if you need more room. I use two of TT's light weight skins, carry a water bottle in one and snacks in the other when out for a longish shoot.
My evening, low light kit is usually 3 or 4 primes, I don't have any f2.8 zooms as they are too bulky/heavy for me. This kit is much lighter and has plenty of extra room, enough for a 2nd body if needed.
Good luck choosing,