Subdividing Causes Strange Edges / Issues on Shape So I have this flat shape, and I'm trying to make it 3D. It's pretty round and has a ton of vertices. My end goal is to have the 3D shape with smooth edges.



I approached this by pressing ALT+F to fill the shape. It created a bunch of faces that don't look too clean.



Then I extruded the shape once forward, and once back (from the original shape) so that it was "3D". This is close to what I want, but I want it to have a subdivision modifier, so the edges look smooth.



I then applied a subdivision modifier, and the shape just looks awful. Bumpy and ugly.


If I do "F" instead of ALT +F, it still produces a poor result.


I've tried looking on this forum for solutions to similar issues, but so far not much has worked. I hope the images are enough to paint my issue, and give an idea of what I'm trying to achieve, any help would be appreciated.
It's not the best topology but just quick example.

First thing I've done was to delete half of the mesh and add Mirror modifier to reduce work.

Next I've created Outer Edge Loop just by extruding vertices.

In the same manner I've filled rest of the mesh with faces with some Reduction Loops, this was needed for making all of the faces quads (more on this you can find on topologyguides.com).

I haven't used any "automatic" methods, it's just extruding E and filling F with a little help from F2 add-on. It's all manual work.