Yes, you should definitely take into account your climate.  Since we do not know where you live, the latitude or the pitch of your roof, it is difficult to be very specific.  In most cases in the South it is better to avoid openings that can not be shaded easily.  Vertical glass is usually better but with more and more kitchens being buried in the middle of the house having a window is not always possible.  The pitch of your roof may not be suitable for installing some models.  Skylights on flat roofs should be installed on a raised curb.  Give us some more info regarding your application so we can be more specific.