after all that time in the lonely wilderness, half dome will seem anti-climactic with all the hordes of deoderized day hikers squawking on the trail. it's just not the same.
i'd skip half dome, set up a plan to go over red peak pass and exit mono meadows, but if the pass seems too difficult at the time skirt around the front (north side) of the clark range to get there.
probably best to set your pick-up for the valley though. not much to do on the side of the road at mono. maybe take the shuttle bus down to meet your friends.
come to think of it, if you don't do red peak pass, you should probably just hike straight down to the valley.