For a uniform look you would want the fancy, Or as we refer to it here Cabinet Grade wood.

Far less defects, I found a photo to use as an example showing Maple and the difference between the grades The same principle can be applied to all cabinet wood.

If you plan to paint the cabinets then "plain" would work just fine. But if you plan to stain and finish them to show the woods grain then always go with the fancy, select, cabinet grade woods.

To get heart wood you gotta pay for heart wood...the "regular" cherry is going to have a lot of variation in grain/color/sap/pitch pockets etc

i am no expert but i did tons of research before ordering my new cabinets. my understanding is that for a uniform look, maple would be your best bet. one of the reasons people choose cherry and hickory is for the variation. cherry will darken over the years as well. possibly the look you want isn't the vision the designer has?
also heart of pine floors should has a pretty good variation as well so if you want uniformity, maybe an oak or maple?

I have Amish made natural cherry cabinets. The upcharge for select/premium wood was 25% when I ordered my cabinets 3 years ago. I would definitly pay the upcharge if doing a kitchen in cherry again. My cabinets do show the grain but they are very uniform as far as the color goes. They have darkened a bit but mostly the natural color just gets warmer and richer looking.

Let me know if you want me to post a picture of my cabinets.

I have natural cherry that is pretty uniform and I would not want sapwood. I would talk to the dealer about the cost of a light to medium stain. It can even out the sapwood but still let the beautiful grain show. Ask to see samples.