From my point of view.
Had Labradors for years.
All round family dogs wouldn't hurt kids or adults. Strong bark behide solid door nobody knows what sort of dog especially someone who's doing break in.
If stranger looks over sees a good size dog that barks alittle may think twice. They not know only get licked to death

I'd put beware dogs signs up make look like unfriendly dog but tell people who you want to know it's harmless. All on looks.
My husband comes late in from local pub I know when the gate goes at 11.30 pm Poppy and Troy barks let me know someone their They only bark for a minute thats all I need though. . I have no problem with that because maybe just that one time it's not him it a stranger trying break in.