The issue is that your base mesh has kind of a messy situation going on at its outer edges.
Instead of using Mesh (Mesh Brep) - which is not the best way to get a mesh if you rely on a clean topology -, I like to construct a clean mesh manually!
This way you retain much more control over the its topology and thus final outcome.
Since you want a filleted situation where the mesh is anchored, I’d do that part later in Kangaroo with the help of targeted anchors, and start out with a chamfered polygon instead. Meshes are edgy things and you need huge amounts of subdivisions to reproduce round geometries, however while starting out you practically always want to have a simple, low poly mesh that is still easily modifiable.
From the chamfered polygonal polyline, you can construct individual quad meshes.
These can be joined and welded to form a bigger mesh, that can in turn be subdivided further.
After carefully defining the Kangaroo goal objects, it should do the rest.
If you do dial up the subdivisions of the mesh, you may also need to adjust the Kangaroo goal values!
You could probably also have remeshed your base mesh with the QRemesh (Quad Remesh) component, but again it’s often times better to have more control.
After all, the initial quad layout hugely influences the final outcome! Not only does it dictate the overall mesh pattern, but also how the mesh is relaxed by Kangaroo.
I’ve laid the mesh out like this, but it surely is not the only way to do it! There are other ways (or patterns) to design the initial quads that in turn produce varied end results of the vaulted structure. Check this out!
Apart from quads, you could also explore tris (triangles) or even ngons (hexagonal or other).
gridshel-kangroo-2.gh (28.0 KB)