Regarding music, hope they don't have 'Praise my soul the King of Heaven' - it's mostly in unison and cripples the bases. IMHO, it was chosen for weddings only by those who only darkened the doors for hatching, matching and despatchings.
My favourites would be
Minuet? Berenice - Handel
O Perfect Love all human thought transcending
Come Holy Ghost or God be in my head during the signing of the registers to shut people up and stop them talking loudly
Psalm 121 - I will lift mine eyes unto the hills, to a lovely chant from the manuscript psalter
Love Divine - but can't decide between the tunes Love Divine or Blaenwern, which became very popular in the 70s
Mendelssohn's Wedding March
Any pauses during the signing of the registers would be filled by Mendelssohn's organ sonata's - my favourite being the 2 in D Minor.
BUT not, not absoultely not, Widor's toccata. Our organist hated it and used to tell people that asked for it that he couldn't play it. Don't know if it was true or not. To me it sounds like something 1 step away from I do like to be beside the seaside.
Sorry, mispent youth as a head chorister, and withdrawal symptoms from not having a day with a big frock, and only the said service. The organist had broken his hip and was sacked by the vicar after over 50 years as organist and deputy. Would have been heart-breaking to have someone else playing, bit like not having df give me away.