There are always going to be people you cannot make happy.
When hubby and I got married, I had some in-law drama. Mostly my mother-in-law having definite ideas on how things should be done. Her third wedding was an affair where she did most of the cooking including baking her own cake. She also made her own dress and those of her daughters. Needless to say, she kept trying to get Hubby to get me to agree to do my own cooking and she'd make my dress. I gave her a chance - I sent her pictures of what I wanted. Every time I did, she would try to steer me in a different direction, towards what she wanted. So I decided just to do it my way. Put my foot down about cooking in my gorgeous white gown. Ordered a cake. Found the most gorgeous gown. Oh how I loved it - and she tried the whole time I was going in for fittings and such to get my money back and go thrift store shopping to find a less expensive one.
We had a small church ceremony planned near our home and were still debating our reception options when my father generously offered to pay for the ceremony with one condition- we had to move the wedding to Vegas, a more neutral territory (bad blood between my parents ever since they split when I was 4). Mother-in-law threw a bit of a tantrum. To this day, I still don't know why considering everyone had to travel to our wedding anyway. Plus, he was willing to pay for anywhere I wanted so I was able to have the wedding I always dreamed of in a gorgeous lakeside garden ceremony with some Vegas kitch thrown in for the fun of it. Hubs didn't care as long as it was what I wanted. So when my maid of honor, who had moved to Texas and ended up not being able to come to the wedding had to back out, I asked hubs' 2 younger sisters to stand in as bridesmaids. MIL took the Vegas location and ran with it. Knowing it was a garden location off strip, she found these old cocktail waitress dresses for her daughters (who were 14 and 16 btw) and sent me the pictures. Dear lord. They were the most hideous taffeta creations ever. And being a pretty laid back bride, I only specified they be royal, cobalt, or navy blue and appropriate for an early evening/late afternoon garden wedding. And yes, I used GARDEN as much with her as I just have here lol. Needless to say, I was scouring my town and the next town over 1 week before my wedding, trying to find something age and occasion appropriate. Thank God for Ross. Last minute dresses were not in the budget but I found two that even matched even though I had to dye them blue since they were ivory.
By that time, I was simply determined to get through the day without losing my cool. I did it too even though I nearly lost it when I found out my dress was ruined right before the ceremony with a huge swathe of grease or oil because the limo driver (Elvis impersonator - go figure lol) failed to clean inside the door well of the car before anyone got in. I just decided "screw everyone and everything else, we're getting married and that's all that matters."
So, my advice is just to let the little things go. Yes, it's your wedding day. Yes you want it to be the way you want it. But some things aren't getting upset about when you remember it's about you and your husband to be and celebrating your life together. If FDIL needs to have control of her and her daughters hair, let her. It won't ruin your pictures because hopefully all you remember is your joy and happiness. Your FSIL will probably regret not giving a speech once he gets past the bitterness of his failed marriage. Above all, don't let them see how badly they make you feel or else they will feel justified.