It could be argued that fewer stretch goals would result in fewer backers, and that would make it more difficult for all Kickstarters to get funded...especially the smaller, lesser-known ones. You would risk trading the disappointment of shipping delays for the greater disappointment of not getting funded in the first place.
I'm not sure what the answer is, but I'm not a content creator (on Kickstarter or otherwise). I'll trust the advice of
@Morrus and
@MatthewJHanson on this subject, since I've backed their projects before and I've yet to be disappointed.