This is the back bone of what you are ultimately looking for and should be the first to think about:
-Does the photographer have good quality photos (are the bright enough but not too bright, do they have an orange tinge etc.)
-Do the photos have an altered effect on them, making them trendy but not timeless?
-Does the photographer’s work have the style you are looking for? (All posed, all photojournalism or a mix of both)
-Is the photographer’s work consistent or does the style of the work seem to change with every album?
-Do you notice unattractive blemishes, distracting backgrounds or awkward poses in the photos?
-Is there a guarantee that the second shooter’s work is on par with the main photographer’s work?