Well, I'm over 60 but make my own clothes and love a good bit of tailoring.
The problem with light grey is that it was very close to to the colour of morning suits. In my family, even the next generation - the grooms wear morning suits (not hired, their own) so a grey suit is just too wedding-y. bUt pink is fine!
Personally, I love tailored dresses and would never wear trousers as formal wear unless it were the full-on style of the 2nd photo in the 1st post which looks like really really stylish drag (Marlene Dietrich style) - but not for a wedding if you're not the groom.
Have a good time, OP !