The reason spd type pedals aren't included with road bikes is that the pedal / shoe selection is interdependent. A larger platform needs to be matched with a softer shoe and a smaller platform with a more rigid one to get the same pedaling effeciency and comfort.
You can make further selections based on how long you plan to stay clipped in at one time and whatever else the shoes have to do, but matching a small platform pedal to a soft shoe just doesn't work well for any extended period of time.
SPD-SL style pedals are road racing pedals and the shoes intended for those are so stiff you'll have to bring a second pair of footwear on a tour or go barefoot off the bike.
Suggest you drop by a good shop, bring the bike, and explain the issues and what your objectives are.