A way for my sim guests to actually sit in the front row of a wedding. They always choose the seats way in the back away from the arch!
Not a hack, but you can do this by making the guests selectable using testing cheats. Have them sit in the correct chairs, then have the couple select Get Married on the wedding arch. The guests should have "Sit" in their queue, then "Watch". If you cancel the Sit action, they will will stay in their seat and watch the ceremony. Occasionally, a few may stand up to move, but then you can just direct them to sit again.
I'm a little more picky about this because I take wedding pictures of my sims, so I want precise seating arrangements. In this pic, I had his family on his side, hers on her side. They all stayed in the correct seats and applauded at the end, as you can see.
I could really do with a mod which enables a random chance of parents kicking their teens out if their relationship is terrible, they have abysmal grades and are lazy rebelds. Not because I want my teen sims to suffer, but because is something I see more often than runaways. Do not peg me as heartless. It just makes more sense to me.
In this house, we respect and treasure all Pleasantview, Veronaville and Strangetown pre-mades. Is that clear?