"Efficiently" is a concept defined only by your target. If your target is economic value, then, sure this kind of auction does a pretty good job at allocating

"Efficiently" is a concept defined only by your target. If your target is economic value, then, sure this kind of auction does a pretty good job at allocating efficiently with respect to it. If your target is something like desire-satisfaction, or promoting novelty/creative use, then it might be worth trying to think about ways to preferentially allocate to people willing to put in more effort too, or, e.g., introduce some kind of lottery system for some domains for non-commercial uses.