My ring was customized by them with some changes in their existing design I saw on their instagram. It's in 18k white and rose gold mix, and the small diamonds on the sides are their Decagon cut. I know in their petite series, the bandwidth is usually about 1.1-1.3mm then they will make it proportional to the size of your centre diamond. I believe mine is 1.2mm.
My ring top view was inspired from this. It's a knife edge uniform band (not tapered). For these thinner bands, they recommend not to have it tapered as there's not much space left for it to go thick to thin. I rem they had a rounded version of it too, but we chose the knife edge design as it looked more sleek.
FYI, in-between the small decagon diamonds on the band, you can opt to have those ''cutting design''. The jagged design on the band. At first we thought it might be uncomfortable but after trying on the actual sample, it's ok. But in the end we decided to opt for the plain knife edge one to make the design more simple. Btw, you can also choose the amount of spacing gap you want between each of the small decagons too.
Then the side view we picked this design (but changed the bottom of the crown to have an ''x'' intersection).
We left the bottom 1/4 part of the band to be plain so that it can be resized in the future if needed.
So my ring design is actually like a mix of different parts of their designs

But you can customize each part to your preference. I suggest looking for Avery. She helped me with my design and have me some good suggestions.
They got a ring design video too with different explaining different parts of the ring. This might be helpful for you to know your options. The videos have part 1,2,3, etc.