I compiled UE4 with VS2017 and I must say intellisense support has improved drastically. Usually it took me about 25 minutes to load the intellisense in the Engine github project to compile. Now it took less than 10 minutes. Also when I created a project I get very fast suggestions when typing.
Haven’t tried out IWYU (include what you use) yet but I will soon.
Btw, that thing with the /Yu I used back in 2015 to get faster intellisense, but in 2017 I don’t need to use it anymore!