What is being done about server stability?

With these past two DLCs the has become very unstable. It seems like every other game I’m crashing out or my teammates​ are. It makes playing any sort of ranked game like playing Russian roulette. 343 has said nothing about why these things are happening or what they are doing to fix this issue. I love this game, but it is so hard to sit down and enjoy playing it in its current because of these issues.