Storm as Gambit's "Best Woman" makes the most sense, Laura's been very close with Remy in recent years thanks to Liu. Would've loved Wolverine, but he's strange when it comes to weddings, Bishop was very close with Gambit but they've hardly said anything to each other since X-Treme. Jubilee would've been a candidate too maybe?
For Rogue, Nightcrawler is family, so yes, but Iceman?...yes and no...I mean that road trip story was such a long time ago, Rogue and Bobby haven't really had any meaningful interactions since. With Rogue's friendships, I'd still say Storm, Wolverine, Colossus, Kitty, Nightcrawler, Psylocke and Rachel have had a lot more history with Rogue ahead of Iceman, especially the 80's. But I suppose Guggenheim had that story arc where Iceman and Rogue were organising a rescue team, so yeah, why not I guess...