To get to the point where you're going overnight, you want to work towards touching the controls less and less. Make some ribs and once everything's stable walk away for two hours and see what happens. Or at least commit to looking at the temps but not touching the vents. You might be surprised to what extent the temps will drift one way and then back another even if you don't touch anything.
Once you get to the point where you can keep the smoker within some acceptable limits for say, three hours at a stretch you can try an overnight cook where you set your alarm for every two hours and run out and verify everything's OK and then run back into bed. Then you can start stretching out that alarm time until you're just getting up once at 3:00am. I don't see any point in pushing it past that - after a while you'll be able to check the smoker and get back to bed without even remembering it.
And yeah, butts can put up with a lot of abuse, so they're good for this stuff.
One last thought... if you're going to be leaving the smoker unattended for any length of time think about the worst case scenario. You can find rare horror stories of some dog knocking the smoker over to get at the meat or whatever. If you're cooking on a wooden deck that's next to your wood sided house or something... think that through, OK?