I have...but first, you might try finding powdered sugar without cornstarch. It's possible that is contributing to your dislike of the flavor. There are a few organic ones out there...but even those seem to be replacing cornstarch with tapioca starch. If you have a Vitamix, you can make your own powdered sugar by zapping regular granulated sugar. The icing will still be overwhelmingly sweet (one of the reasons I no longer make cream cheese icing with that alone).
Newer eggs whites have less water so take that into consideration.
As far as flavoring, I prefer fresh lemon juice to cut the sweetness. It never seemed to impact the cookie flavor.
Sugar Baby icing used both vanilla and a bit of almond extract, which also seemed to mask the powdered sugar flavor.
Not sure of your egg source...lots of warnings re: raw eggs due to Salmonella. Those sites recommend using pasteurized egg whites, but I've never had luck with that for buttercream icing, so never used it for cookie icing.