I made a speech at my eldest Son’s wedding in Darwin, only because the Father of his Bride had already passed away and her Mother was not keen. It was a hot day (Darwin, after all) and I had more than a few beers. My other Son warned me not to say anything about his Mother, Mrs Fox the Second, mother of all my kids, so I complied and ignored her completely. Everyone noted that and thought I was just being my normal prickish self.
I have also given the Father of the Bride speech at the daughters wedding. Less said of that the better.
So my advice, is to mention everyone, only say nice things, don’t try to be funny and leave all drinking until after the speech.