First off, I'm very excited about V2, and it's been an amazing release. Congratulations Serif!
One change that I would like to see, which there has also been discussions about in V1, is better ways for managing overprint and spot colors. The only way to enable overprint in Designer right now is by creating a global color with overprint enabled and using this color. It would make more sense to handle it similar to Adobe Illustrator, where overprint can be enabled individually for fills and strokes of a selected (or group of selected) objects. This would make overprinting more transparent and easier to manage.