How do I repeat my script/macro across all selected objects?

Question

I am trying to create an automated LOD process within Blender, that takes a mesh, creates a group using the mesh's name, renames the mesh to '_LOD0', adds a Decimation modifier and then creates 3 more meshes with progressively higher Decimation modifiers and LOD numbers:

This seems to work fine for one object selected, but if I have multiple objects selected it puts all of the objects in the same group, and makes more objects than I want, and also doesn't add the decimate modifiers correctly:

I know that bpy.ops isn't the most optimized way to do this, but that's not a huge concern for me, I just need it to work. If anyone can point me in the right direction on how to achieve these goals it would be much appreciated, thanks!

import bpy

if bpy.context.selected_objects != []:
    for obj in bpy.context.selected_objects:
        bpy.context.scene.objects.active = obj
        bpy.context.object.show_wire = True
        bpy.context.object.show_all_edges = True
        bpy.ops.group.create(name=bpy.context.object.name)
        bpy.ops.object.modifier_add(type='DECIMATE')
        bpy.context.object.modifiers["Decimate"].use_collapse_triangulate = True
        bpy.context.scene.rno_bool_keepIndex = False
        bpy.context.scene.rno_str_subfix = "_LOD0"
        bpy.ops.object.rno_add_subfix_prefix()
        bpy.ops.object.duplicate_move(OBJECT_OT_duplicate={"linked":False, "mode":'TRANSLATION'}, TRANSFORM_OT_translate={"value":(0, 0.1, 0), "constraint_axis":(False, True, False), "constraint_orientation":'GLOBAL', "mirror":False, "proportional":'DISABLED', "proportional_edit_falloff":'SMOOTH', "proportional_size":1, "snap":False, "snap_target":'CLOSEST', "snap_point":(0, 0, 0), "snap_align":False, "snap_normal":(0, 0, 0), "gpencil_strokes":False, "texture_space":False, "remove_on_cancel":False, "release_confirm":False, "use_accurate":False})
        bpy.context.object.modifiers["Decimate"].ratio = 0.5
        bpy.ops.mesh.customdata_custom_splitnormals_clear()
        bpy.context.object.data.auto_smooth_angle = 0.785398
        bpy.context.scene.rno_str_old_string = "LOD0.001"
        bpy.context.scene.rno_str_new_string = "LOD1"
        bpy.ops.object.rno_replace_in_name()
        bpy.ops.object.duplicate_move(OBJECT_OT_duplicate={"linked":False, "mode":'TRANSLATION'}, TRANSFORM_OT_translate={"value":(0, 0.1, 0), "constraint_axis":(False, True, False), "constraint_orientation":'GLOBAL', "mirror":False, "proportional":'DISABLED', "proportional_edit_falloff":'SMOOTH', "proportional_size":1, "snap":False, "snap_target":'CLOSEST', "snap_point":(0, 0, 0), "snap_align":False, "snap_normal":(0, 0, 0), "gpencil_strokes":False, "texture_space":False, "remove_on_cancel":False, "release_confirm":False, "use_accurate":False})
        bpy.context.object.modifiers["Decimate"].ratio = 0.25
        bpy.context.object.data.auto_smooth_angle = 1.53589
        bpy.context.scene.rno_str_old_string = "LOD1.001"
        bpy.context.scene.rno_str_new_string = "LOD2"
        bpy.ops.object.rno_replace_in_name()
        bpy.ops.object.duplicate_move(OBJECT_OT_duplicate={"linked":False, "mode":'TRANSLATION'}, TRANSFORM_OT_translate={"value":(0, 0.1, 0), "constraint_axis":(False, True, False), "constraint_orientation":'GLOBAL', "mirror":False, "proportional":'DISABLED', "proportional_edit_falloff":'SMOOTH', "proportional_size":1, "snap":False, "snap_target":'CLOSEST', "snap_point":(0, 0, 0), "snap_align":False, "snap_normal":(0, 0, 0), "gpencil_strokes":False, "texture_space":False, "remove_on_cancel":False, "release_confirm":False, "use_accurate":False})
        bpy.context.object.modifiers["Decimate"].ratio = 0.1
        bpy.context.object.data.auto_smooth_angle = 2.0944
        bpy.context.scene.rno_str_old_string = "LOD2.001"
        bpy.context.scene.rno_str_new_string = "LOD3"
        bpy.ops.object.rno_replace_in_name()

(It may not matter for what I'm asking, but I'm referencing a batch renaming addon in my code called 'vtools_renameObjects' - dropbox)