I've been to a dry wedding. I quite liked the idea, as I was pregnant at the time, and it meant I wouldn't be surrounded by pissed people all day. There was a good selection of non alcoholic drinks, including lots of mango lassi, and the food was incredible.
The main problem was, though, that everyone left virtually straight after the meal. Without booze to fuel dancing/chit chat/mingling, people stood around awkwardly and then decided to go home. DH and I were some of the last to leave and we were home by 6pm IIRC.
I guess it's quite sad that as a culture we need booze to make social situations flow better, but that's the way it is. It's not even about being pissed, it's more about the way booze affects the flow of an event itself.
If there's a bar, it's a focal point. People offer to buy each other drinks, get chatting there, and stand around holding glasses of champagne etc. Without the lubricant of booze - at least at the wedding I was at - people just didn't mingle. They sat at their tables with juice and then went home.
I'm not sure how you can tackle that without it looking awkward. Magicians are cringey. I'd be up for an "organised" dance, ceidlih style, to get people up and moving, but I know my DH and most of my friends would be aghast at the idea of dancing without a pint or two for courage. It's a tricky one!
Aside from the booze issue, just to echo what others have said - make sure there's lots of food, avoid hanging around, don't do endless staged photos and also avoid bloody twee "sweetie buffets." They're everywhere these days and are a bit of a cliche IMO - better things to spend money on!