Personally, I would do it under all cabinets with the disclaimer that they can be dimmed or brightened as needed. The metal will reflect the light but its important for consistency and to be able to see without having to turn on all the lights.

Also, people don't tell you think but the microwave has a light under it and unless its the same color it stands out like a sore thumb. But, you can switch it out. For instance in my house it is a fairly neutral white light under my cabinets but the microwave is yellow as can be. So i swapped it out. just make sure to look up replacements parts for you model to make sure you are getting the right kind.

Diffusion channel: Channels for LED Tape Lighting - Lee Valley Tools

I would use the diffusion channel for all the LEDs, not just the segment over the sink. Tape light is great but it can be harsh reflecting off the countertop -- the diffusion channel will soften the light.

Be sure to use diffusers. My LED strip lighting was installed 7 years ago and I was not advised about them. The bare strips are fine when working in the kitchen, great for light, but the view from sitting in the family room is awful.

following

Ask your electrician to install a flush mount fixture on the same circuit that's rated for damp/wet locations:

https://www.build.com/wac-lighting-fm-05sq-9/s1568799?uid=3747887

https://www.build.com/wac-lighting-fm-05rn-9/s1568798?uid=3747881

I got some strips from Amazon, they teeny tiny, can not see them. $20 with remote control.

https://www.amazon.com/gp/product/B07TN5HNPN/ref=ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1

Thanks all for your advise! Spoke to a lighting store & they also said to put lights above the sink. Also getting the diffusers per your recos. :)