Yes what you said about rocker is correct, its better in the chop, but it also comes with the downside of not having as much up wind ability. This is why wake boards are not recommended to learn on.
If your are riding in choppy conditions which are gusty or over powered a flatter board with a bit more flex is advisable, making it easier to keep your upwind ground. Many board designs today using rocker are now putting channels in their boards to disperse water in a more precise ways making landings smoother and softer compared to a flat based board with rocker whereby water is not being channeled in as an accurate manner. Also another upside of having channels in a board is having more hold/ grip on the waters surface increasing turning and also adds to upwind hold.
outline and shape determines many things such as speed, turning and pop. Using the rockerd board again as an example. Looking at a rockerd boards outline, it is generally thicker in the middle and thinner at the tips (also again helping with the distribution of water when landing)
because a rockerd board is curved the middle sits lower in the water making the board slower (making a flatter board a better light wind option) a board with less rocker will be faster due to the board not sitting as low in the water, and hence allowing it to hold its surface tension longer on the waters surface.
A board which is flat but has allot of flex can handle choppy conditions well when ridden with a bit more weight than normal on the back foot. A board with more flex when edging hard can develop a bit of rocker (due to the nature of the flex in some boards this may vary) helping the board cut through the chop better compared to a board with more stiffness.
i seriously could go on for pages about board design, but unfortunately in this day and age of technology and science everything is just to complicated.
but if it comes down to it, its how you ride the board not the board its self for all we know the latest reviews could be written by a kook of a bloke which couldn't tell the difference between a blank of wood with foot straps and one of the best boards on the market today.
ride with what you've got, have fun