I think Aulani is decent SAP for WDW, even if you can't book at WDW at 11 months out. It may not always get you the cheapest rooms, but I don't view that as the primary goal of SAP. To me, SAP means cheap points that I can use to book something satisfactory. In the Westin system we own a Westin with cheap dues in the AZ desert and can use it at 8 months out in Hawaii or the Caribbean where dues are double (owners book 12 months out). I don't always necessarily get my first choice of summer week, room size, or view category, but I can almost always get a summer week in a room/view that makes the entire family happy (I've been doing it for ~15 years and visited the home resort just once). For us, it's similar with the Aulani subsidized when it comes to WDW, although we also own at multiple other home resorts too and also intend to visit Aulani every 3-4 years. Aulani represents about 50% of our total points, so it's meaningful. Given most others'
DVC booking preferences with home resorts, we can actually use Aulani points at WDW for larger rooms with nicer views so it makes those stays more memorable than the "cheap" ones where we use our home resort points.
The only reason to worry about availability at 7 months at a place like SSR is if you want a studio, or a 2BR around the holiday season in Nov-Dec. If a 1BR suits your needs, you will very likely find one at the 7-month window pretty much anytime of the year in both view categories. And if you can book SSR at one of your top 3 room choices as a backup at 7 months out with Aulani points, then it really doesn't matter if your SAP are Aulani or SSR, at least from a WDW availability perspective... Just my point of view.
Regarding your question what is hard or easy to book at 7 months out, check out these tables for an initial indication. If the number is not "7" you may have trouble booking. Tables are based on 5-year historical averages and things can and do change over time.
https://www.dvcfieldguide.com/availability-tables