I think the answer would differentiate based on your needs.
If you are looking to save money, I'd recommend ordering the OnePlus 5T. OnePlus usually discontinues their current product right before their new line releases; so if you do indeed decide on the 5T, go for it! It has flagship-level specs but is at a more affordable price than, say, the Pixel 2. It has a good display, the camera is decent, and Oxygen OS is a great system and close to stock, I've heard.
That being said, if you can get the Pixel 2 at a discount and do not mind spending a bit more money, that is a good option as well. The smaller 2 would be a bit cheaper; though they have the same software, camera hardware, etc. Stock Android is awesome; battery life is good; and the experience is smooth.
Keep us posted on what you decide!