The way I see it, jerseys have to fit well, last thing you want is your jersey flapping like a flag, rolling up your back and exposing your skin or swinging around with the weight of things you have in your pockets. I like them firm against my skin without making breathing even a bit laborious. Remember, you will be wearing a bib and a HR transmiter under the jersey.
The Club Jersey
Of course, they must suck the sweat off your skin (simple terms here) and let it evaporate into the air. I don't want to ride with my jersey soacked in sweat (extra weight!!), a good way to see how it works is to have a look at other rider's jersey during a hard and hot ride. If they are wearing a jersey made with quality material, you will see the salt marks on them as only the water from the sweat will evaporate.
Any coulor, as long as it is black!