I look at bunkering from a number of perspectives;
1/ They are that odd golf/architectural vestige of original golf (linksland) that although probably not completely necessary to golf as a few other features--eg tees, fairways, greens, have become almost an essential element in golf and architecture (although, again, frankly not completely necessary).
2/ Bunkering is truly one of a golf architect/designer's best expressions of both strategic creation and function as well as artistic expression.
3/ The look of them. Are they such that they appear naturally occuring or somewhat so (both shapes and grass surrounds) or are they artistically appearing or are they artifically appearing (man-made looking). This would be the aesthetic area of bunkering.
4/ The function of them. I look at this area in two ways which always includes their placement.
A/ the playability of their sand areas. Is it immaculately maintained and consequently easier to play from, or is the sand area less maintained, more random and iffy and consequently harder to play from.
B/ the playability of their overall architecture. Is it architecturally simple and shallow and consequently easier to play from, or, is it architecturally complex, deeper etc and consequently harder to play from.
Those four areas and a few subsets is the way I look at bunkers and particularly their function and playability. There's no question to me that generally the more natural appearance is more appealing to me and that the more difficult sand areas as well as the deeper and more complex architecture of bunkering (particularly complexity and depth dimension) makes for better and more meaninful strategy and playability.