Daniel & Amber were going to get married in some little church, weren't they? Pretty sure that was the wedding that Daniel missed because he was busy falling down the well & in love with Imogen & Amber ended up sleeping with Josh afterwards.
I think Didge & Declan also got married somewhere else... There's definitely precedent for nuptials occurring outside of the complex!
I'm envisioning Elly & Mark by the lake with folding chairs in rows next to a white carpet along the aisle. If it weren't for the whole Sonya storyline they'd have Nell throwing pink rose petals from a little basket. Y'know, all the bland, stereotypically twee stuff!