I enjoy weddings - here are some of the things that help me enjoy them more - just so you know, DD is currently 4, and has been to about 12 weddings (despite us being far from young when she was born):
Local is good (especially with a child)
Having lots of my friends there - I know that realistically, on the day, I'm going to spend very little time with the bride and groom (and that's OK), so it's great to have friends to catch up with.
Somewhere urban makes it easier to deal with a child unless the venue is very child friendly.
I really really appreciate a rough timetable of what is happening when, especially with a child - if I know when the critical bits are, I can try to feed her at other times (if the meal times are unusual), take her to a park for a run around if necessary, find her some quiet space when that would help etc.
Having a space at your venue where those with children can take a child who is struggling to behave/needs somewhere less overwhelming. Some of the churches near here have rooms which overlook the main church with a sound relay so you can hear what's happening. That's the ideal, but not always possible!
I realise these are mostly about children, and you're very welcome to have planned a child-free day - we've been to a couple of family weddings where there were only family children, and then only a couple of them. That's actually harder for us than when there are more children to play with. Of course, the day isn't about us, and we'll do our best to keep DD under control in public (!), but we got married before DD came along, so a lot of this didn't occur to us then.