I’ve been advising my consulting clients for years to avoid Aperture. Not on the feature set; that was always a better/worse thing depending on one’s own workflow needs, but on the attitude towards professional needs.
The problem with EOLing professional software is that some users have invested years of learning and workflow techniques. When a vendor abandons the software, that investment is doomed.
While Aperture will soon be unavailable for sale, it’s not clear how long it will continue to function as new and increasingly buggy OS X software releases are delivered. But it’s a safe bet to say Aperture fixes will be a non-priority, so if your workflow relies on Aperture, it’s a good idea to start transitioning away from it now, possibly locking down a machine for existing work (no updates to anything, a “toaster”)—just as one might do with any dedicated printing setup or similar “must work this way a long time” setup.