Super quick engagement helps when riding over obstacles, and the tool free service makes it a breeze to clean your hubs after a muddy race.
The Pinnacle CX has a 29mm wide rim with a 32mm radius for a rim bed, larger cyclocross tires fit perfectly and receive edge to edge gluing for a more secure adhesion. This allows you to run lower pressure without fear of rolling a tire off the rim. In cyclocross a tubular tire is still a distinct advantage.
Yes, the Pinnacle Hookless is a great option for a cyclocross wheel (that can also be used for gravel riding). However, if you are looking for every advantage possible for cyclocross, then a tubular is a better option.
It's impossible to answer that question as it will depend on tire tread, weight, course conditions, etc. Dialing in tire selection and pressure is one the major factors to cyclocross success, so this is something you should spend some time on this. It will be to your advantage!