So you have to agree with reviewers only? I agree the majority may not but some may consider them negatives so...
I have detailed at length, multiple times, why sd cards are a detraction from any device they are found on. I have also detailed numerous times why I dislike off screen buttons and fingerprint sensors on the front of devices and there are many, many people that also prefer rear fingerprint sensors and/or screen buttons.
I am for sure not alone on preferring a "flat" screen to the edged panels, there are hundreds if not thousands or more that share that opinion with me within this community alone.
But the entire list of things that I would have changed if I were designing the S7 for myself is:
Hardware:
Use a "flat" screen.
Use the stock Android on screen buttons in the correct order with no modifications.
Use a metal or plastic body, trying to avoid the fisher price look and feel.
Put the fingerprint scanner on the back, similar to where it is on Nexus and Pixel devices.
Use USB 3.0 with a type C connector, disinclude support for Qualcomm Quickcharge 2.0 and include support for Power Delivery.
Remove the microSD card slot and offer a 64 or 128 GB option.
Remove the Samsung logo from the front of the device.
Fix the audio, both headphone and speaker sound is terrible.
Include dual front facing speakers, attempting to meet or beat the Axon 7.
Software:
Guarantee major updates within 28 days of public system images being posted for at least two years.
Guarantee monthly updates within 72 hours of public release for at least three years.
Slim down Touchwiz - a lot. Grace UX was a good start for the Note 7, bring that over and then start reading about what OnePlus did with the software on the 3T, both from a resource management and animation design perspective.
Eliminate most of the duplicated effort system apps.
Eliminate most bloatware.
I would definitely keep the camera, it's awesome - possibly fix the over-saturation in post processing and keep it too fast. I would definitely keep the display quality, still the most accurate Android phone, most accurate AMOLED phone and it's working, so keep it up.