With the 2016 iphone, one should not be concerned about major issues since it's basically an improvement over the 2015. The 2017 on the other hand is a different matter.
Waiting a few weeks is not going to do much. I imagine there will be significant issues with the 2017 that won't be limited to software. Look at the iPhone 6. People who have this device still have issues with the screen. While those with the 6+ do not. However, one's best bet is to buy the 2017 model close to Xmas time and definitely get Apple Care or get the 2018 model.
Waiting a few weeks is not going to do much. I imagine there will be significant issues with the 2017 that won't be limited to software. Look at the iPhone 6. People who have this device still have issues with the screen. While those with the 6+ do not. However, one's best bet is to buy the 2017 model close to Xmas time and definitely get Apple Care or get the 2018 model.