Welcome to the forum.
Not necessarily. Make your template from 3/4 mdf and use a plunge router with a bearing guided bit to cut the margins, then you can freehand clearing out the centers of each indent. You have the ridges to support the router, and if not, you can get a piece of Lexan to make an oversized base you can see through. Set the maximum depth on the plunge router, and the intermediate steps will be the in-between steps. That a very interesting tray. I've been thinking and addressing something more like a shallow bowl.A bit with a bearing will only work on the perimeter and only after a perimeter is established. And I would have to use successively longer bits to keep using the established perimeter.
Normalization.I have several routers from dewalt, to festool, to bosch, and hitachi. I also have several sets of guide bushings, but either the bushing is too deep or too shallow. For example, I made a charcuterie tray using a mdf template and a 3/4" dia tray bit. Due to the sizes of the cut outs, I needed an extended base, which I have form my OF 1400. However, the base is around 1/4 thick and the only bushing that I have for a 3/4" dia bit has a projection that is around 1/4", so it doesn't work. I resorted to making an mdf base in two parts: the lower part was planed down to about 1/8 and the upper part remained at 1/4". I then made a cutout in the upper part so that my router could recess indie the upper part, but no pass thru the lower part. I then epoxied them together. Not the best base and not something I want to use much. So, my question is, where can I get custom bushings, or at least bushing that aren't off the shelf at Lowes? I've tried Peachtree, WoodlineUSA, TreelineUSA, and I even reached out to Whiteside and Amana. I saw a thread about busing storage in a pinned post and it appeared that the feller had a lot of different sizes. I'm sure I could find a machine shop and give them the specs, but I bet they'd run $100 ea. Any ideas? Thanks.