Map entity protection. Here's a quick list:
func_breakable
func_breakable_surf
func_brush
func_button
func_conveyor
func_door
func_door_rotating
func_healthcharger
func_lod
func_lookdoor
func_monitor
func_movelinear
func_platrot
func_recharge
func_rot_button
func_rotating
func_tank
func_tankairboatgun
func_tankapcrocket
func_tanklaser
func_tankmortar
func_tankphyscannister
func_tankpulselaser
func_tankrocket
func_tanktrain
func_tracktrain
func_train
func_wall
func_wall_toggle
func_water_analog
momentary_rot_button
cycler
cycler_actor
env_headcrabcanister
generic_actor
item_ammo_crate
item_healthcharger
monster_generic
item_suitcharger
prop_detail
prop_door_rotating
prop_dynamic
prop_dynamic_ornament
prop_dynamic_override
I'm not sure if that covers everything, just a list I stole from a pre-made script that came with a map. I basically want everything protected that comes with the map, except for spawnable items (like on those maps where you can spawn brushes or props). This also should be toggable and maybe have a config server-side where you can set what is protected. Also, you would have to make an exception for gm_construct for the walls (I am not sure what type of entity that is but it's on the list). Maybe per-map configs?! Yay?