The one thing that I hate the most about most romances is when the treat the start of the relationship as the end goal of the story. They just waffle around with will they won't they stuff, get together, and then the story ends.
That is the most boring part of the romance!
Most of the interesting stuff comes with the relationship struggles, and everything that comes after the relationship starts. I much prefer the stories that have characters get together, and stay together, at the beginning, or at the very least, middle of the story.
The other romance trope, that I don't like, is romance for romance sake. There are a lot, A LOT of stories that have romance in them, but for no reason. It doesn't advance plot, it doesn't advance character. So why add it?
And what's even worse is when they combine the two, adding a romance that doesn't need to exist at the very end.