I'm currently shooting wildlife with a Canon 6D + 70-200mm II with a 1.4 III.  Not much reach with this combination so I've considered purchasing the 100-400mm II to use with the 6D.  Instead, should I hold out and wait for the 7d III and use the aformentioned lens combination?  This combination would give me (200*1.4*1.6) 448mm at F4.  Obviously, the combo of the 7D III with the 100-400 II would be ideal but its a cost thing.

Thanks in advance,

Tim