Any better implementation of ExtrudeGeometry?

Certainly, very diverse figures can only be created with modeling tools.

I also like the creation of custom geometries.

Maybe you need special geometries that can be generated with my three.js addons? hofk (Klaus Hoffmeister) · GitHub

See also

THREEf.js/THREEf_90/modifyCreateGeo.html at dev · hofk/THREEf.js · GitHub

Addon. Produces almost infinite many time-varying geometries with functions - #31 by hofk
(Outputs the elementary BufferGeometry definition for a selected time.)

Modify indexed BufferGeometry (mouse or input)
(Modify the geometry)