I'm running Aperture without problems using Sierra on 2010 Mac Pro. I replaced my older Mac Pro with a used 2010 model, put in lots of memory, SSDs, and a high power graphics card. This gives me 3-4 years of supported OS X on a reasonably priced machine. I also allowed me to use the keyboard, mouse and monitor I already had.
Have you considered trying ON1 RAW 2018? It runs on all recent Mac OS X and recent Windows OS versions. To get best performance requires a certain level of graphic card abilities but the 30 day trial allows you to check it out. I plan on using it as my eventual Aperture replacement and am actively planning and preparing for the migration.
ON1 RAW has a Sync function that provides similar results to Lift and Stamp but does not include "batch" cropping.
ON1 is a newly written RAW processor. The 2017 RAW release, while usable, was short of features, sometimes buggy and I don't think ready. Numerous point releases followed by the 2018 RAW release added a lot of needed features and fixed a lot of bugs. However, some people are still having issues and griping about missing features. Others compare it to programs that have years or decades of development. I think this App is already good but has amazing potential to become much better over time.
Below is a list if my likes and dis-likes in no particular order. The list is also not exhaustive.
ON1 pros
A non destructive RAW processor that uses the graphic card for performance.
It is a Browser, not a DAM. Organized your images in the Finder
Move things around in the Finder using the Browser. This helps keep the side car files with the image.
It has a database/catalog feature that is used to speed up searches and preview display.
It stores adjustments in side car files as well as the catalog. Lots of redundancy here.
It stores metadata in industry standard side car files as well as the catalog. More redundancy.
More free presets available than you could ever use. Great for trying different looks quickly.
Great masking features and relatively easy to use.
Lots of training movies available for free.
Buy forever with discounted upgrades, or subscribe and own the current subscribed to release forever without expiration.
Optionally subscribe to a Pro level access and get extended training, access to experts, image critiques, forums.
A user driven feature request.
Lens correction.
ON1 cons
Apertures DAM is better than a Browser.
Still has bugs - one of which is keeping me from jumping into a Aperture to ON1 RAW migration.
Still missing features that more mature programs have.
No Aperture conversion tool. If you want Aperture adjustments baked in, export a TIFF or JPEG from Aperture.
Very basic keyword, metadata and search capabilities
I need to leave Aperture in my work flow until the keyword and metadata features improve.
Lens correction can't find my lens, but it is in the list and can be accessed manually.
The support line is very busy.