I tried to create pointerProp type=bpy.types.CurveProfile (not sure why I shoudl create subclass for it?), but blender would not register this kind of operator property.
Now I tried to use bevel_curve_profile directly in operator draw function:
layout.template_curveprofile(context.tool_settings, “custom_bevel_profile_preset”)
but any changes to curve are gone on operator redo:
It was the same with curve-mapping node in past. I guess operator is undoing any changes to objects, scene, properties, that are not defined in operator itself, before executing itself on prop change.
Testure - yep but it seems curve property is being reset on each operator re-run (when changing operator property)