JB - I think #15 is a good hole that could be great, but suffers as you pointed out. The biggest problem is the houses on the right being overly intrusive, especially the one just to the right of tee. The 2nd biggest problem is as you stated - the fairway width. It is a narrow fairway from tee to green. On the tee, if you miss left or right, you really have little to no recovery shot. On your lay-up shot, you have an unnecessary row of 20 yard long rough to carry and then a narrow fairway. This makes for great tournament golf, but difficult member golf. On the positive side, it does provide great risk/reward in terms of getting home in 2 and has a cool raised green with a false front down to the creek. It is also very picturesque.
In general, I love Muirfield Village - would love to play it again if the unaccompanied rate wasn't so high. Just an unbelievable property and some incredibly good golf holes - especially 3, 5, 9, 10, 11, 14 and 18. Its detractions lie with the housing development that surrounds many of the holes - it really hurts the feel of the place (you never get the sense that you are walking with nature as a result). In addition, while I usually hate trees on a golf course, 16 and 17 need some trees along the outsides of the holes to provide definition (as they feel like prairie holes at the end of a parkland course).
While I see the comparisons with Augusta in terms of #12 and #16, I really don't think it applies otherwise. Both are great places, but the similarities are not much greater than those 2 par 3's.