This is the control/baseline form of my Goon takes a drink series of animations.
There's really nothing to it, it's just a canvas onto which I will paint more detail, so to speak.
I hid the constrains problem here by pasting the picking up keyframe to the putting down keyframe, so it's in the same place. The glass can't be rotated without causing problems once the constraint is set up so I'm stuck with the position his hand is in when he picks up the glass.
I'm thinking of ideas like a drunken guy swinging the glass up, a dirty guy taking a swig and burping, a wired guy necking a shot of espresso, things like that. By adding secondary action to this pose, and tweaking the timing and spacing, I change the character in the shot.