The 70-200 zoom will be my next 'need', and I'm still leaning toward the F4 since I'll be able to use it on the 5d3. If I want more bokeh, I do have a 50mm 1.8 in my bag. My bf has been talking about ordering both, trying them side by side and then returning one. I keep telling him he needs his own 70-200, as sometimes we shoot together, sometimes apart. Plus, we've got multiple lenses right now that are redundant. I've got my 17-55 up on CL, but haven't had any luck selling it thus far. Adorama is offering me a price that is fairly close to my asking price, so I'll probably send it in to them. So I guess my final choice is f4 for me, f2.8 ii for him.
In your situation, I'd get the 70-200 f/4 L ... I know a lot of people say f/4 is not good for wedding photography etc but I've seen photos made by some accomplished photographers, even with a "slow" lens like Tamron 28-300 VC ... one example is this: http://digitalprotalk.blogspot.com/2012/04/test-driving-new-tamron-28-300mm-vc.html
The 70-200 f/4 L, is on sale right now for $1149 (for IS version) and $674 for non-IS ... this one is light on body and light on your purse.
5D MK III, 16-35/2.8 L II, 24-70/2.8 VC, 24-105/4 L IS, 70-200/2.8 L IS II, 100/2.8 L IS, 40/2.8, 50/1.4, 85/1.8, 150-500 OS, 600EX-RTx2, ST-E3-RT, Rokinon 24/3.5 T-S, D7100+18-300 VR, YN568EX, 055CXPRO4+468MGRC2, 190CXPRO4+322RC2, Gorillapod Focus+496RC2, CamRanger, B+W filters, Konova K3/31.5 etc