I'm another one who thinks FDIL (future DIL) is trying to be nice and inclusive (so many grooms' moms complain about being "left out" of the planning!). It may seem as if she's deliberately doing the opposite of what you say and I understand if you're beginning to be irritated. But please remember, she is probably also getting advice from her own mother, plus, perhaps, one or two of her bridesmaids. Besides, it just may be that the two of you have very different tastes and ideas.
Both my DDs sought some advice from me when planning their weddings. But while one of them took a few of my suggestions, the other didn't end up using any, LOL! Both of them had beautiful weddings that suited them and their grooms. Did I ever have a moment when I was disappointed that they didn't opt for some suggestion of mine? Sure. But in the end, I knew it was all ok. You will, too, I'm sure, once the wedding day is here.
For now, I think you should go on answering FDIL's questions, but maybe just briefly. But don't expect her to follow what you say. Or maybe, when you can, throw it back on her. Like if she asks what song you prefer for a certain number and she mentions a classic one and a more modern one, you could simply suggest that she decide what kind of vibe she's going for - traditional or trendy. But please don't put too much weight on this. Just enjoy the wedding and the fact that your son is getting married!