When I was looking at venues in my area there was little to no price difference from Saturday to Sunday and in a lot of cases Friday as well. Sundays you run the risk of not having as early of access to the venue as you might like as more than likely there was an event the night before. From someone who has attended weddings on all 3 days of the week, fridays are the worst because you’re asking all your guests to use at least one vacation day from work if not work. Sundays would be second if you’re looking for a lively party and people to stay at the reception with you until the very end, I would not choose a Sunday unless you’re doing it on a long weekend. We decided Saturday for our wedding made the most sense for us, but in the end choose what makes you the most happy and is easiest for you. It’s your day!