not sure what shotgun your using, but many models have quick set up scope mounts that can be added to them, and removed just as easy, and can make a shotgun with a bead a LOT more accurate, a good LOW magnification scope is nice for closer shots and accuracy
I honestly am NOT fan of buckshot on deer period, or running deer shots, but do know it can be done, its just not for me,
slugs can knock down deer way better than buck shot IF you hit vitals IMO< or even LARGE bones
as you said, just pick your shots well, non one says you HAVE to shoot at every deer in range, so, being more picky is good for both you /deer and Dogs IMO
just remember a slug will travel farther thru things than buck shot will, so watch your backgrounds