Depends on how likely you think you'll be to want the iPhone 7. If the answer is "very likely" then I'd get a 6+ now for sure, knowing you'll skip the 6S+ and then get a 7.
The "S" versions are always nice, but ultimately just evolutionary improvements to the prior model. I wouldn't wait for it at this point.
The "S" versions are always nice, but ultimately just evolutionary improvements to the prior model. I wouldn't wait for it at this point.