Hey, my daughter hasn't hit this stage yet, but I do work with kids, so I know a little about creative discipline. That said, I am not against spanking entirely, but it my be for a consistant issue, and it should never be because you are responding in anger. For instance, if your child is hitting you, you need to respond and say, "It hurts when you hit me." If that doesn't get the message, when your child hits, you might response with an open handed swat between the butt and the knees.
However, I don't know that spanking needs to be your first step. The saftey things aren't an issue, let them have them if they make him feel safe. As far as the sippy cup, what's in it? Juice? Slowly add water to the juice until the cup is just filled with water. I don't think there's any harm in having water to drink during the night.
Also, he doesn't have a concrete since of time, but he does understand "soon". Prep him for all upcoming activities- "In five minutes, we have to put up the toys and go to sleep." A warning lets him switch- melt downs come from feeling a loss of control.
Make bedtime fun with a light up tooth brush he only gets a night, let him pick his PJs and a night time book. Play the same music everynight to help him go to sleep. If the lamp bothers you, put a timer on it, so it will go off after a hour. And I would stay in the room, maybe on the floor, not touching him, until he goes to sleep.
