Refinish stucco on exterior with new texture?
Two long for a comment but I think it answers your questions. From how thin that top coat is and colored below that was probably an over coat, my guess that the old surface was not well prepped or the stucco was put on too dry. 

The first thing you will need is to get all the loose stuff off. I usually use a industrial pressure washer and target any bubbles or flaking areas; at 5000 psi you can rip off an over-coat that is in ok shape and it will etch even a very solid wall. I like this kind of power because it provides a great base for the new coat to stick to. One advantage to a complete over-coat is you can use tint in the mix for color that lasts decades; for light colors it is best to use white Portland cement instead of gray. Now for a smooth surface once the base is prepped I think it's easier as a heavy texture can be tough to maintain a consistent texture unless sprayed. The next step after prepping the base would be to build up the areas that have failed. After that it is time to fill and build a slightly thicker coating, when I have done this I use a little extra cement and water in the mix (with the sand and lime if hand mixing) the extra water helps the mix to flow and makes it easy to trowel with a larger blade leaving a smoother surface that locks into the base.  The one trick when resurfacing I found helpful is with a loaded trowel work it in moving up then smooth it out pulling down this helps to work it into the wall. Note repair those cracks prior to resurfacing or they will show up again. Where I have cracks like this I will strip several inches on either side and really clean it out even surface grinding on occasion and adding mud and mesh this ends up adding strength and it may not crack as bad or at all if the wall is stable. If there is pest damage or rot that should be repaired first or the new surface will crack as the wall moves.