Critique My Job Hunt/application Strategy

Like many, I'm plugging away trying to find work in this terrible market. There's a lot of generic advice out there but I'm hoping for some on my specific situation. I also wonder if some career advice ("apply even if you only meet 70 percent of the qualifications") is outdated due to the current competitive economy. More details inside!

I have the education, skillset, references, portfolio, and experience to be an excellent candidate for a fairly small handful of jobs. I have been searching since March and usually find about 1-2 listings per week that are a good fit.

My strategy thus far has been as follows:

-Use all the online job listing sites/newsletters, my existing network, and direct websites/social media accounts of companies and organizations I'm interested in to find open roles - both local and remote, full-time and part-time.
-Only apply to the jobs where I'm a very good match (80-90 percent of qualifications roughly)
-Apply to jobs even when the wage is less than desirable if it's otherwise a fit.
-Have connections I know make introductions/referrals whenever possible - so far, 4 times.
-Tailor my resume and cover letter very specifically to the job description/keywords, and have my mentors look at it before I submit. I usually spend several hours doing this.
-Have my resume formatted to be compatible with ATS systems.
-Further develop my skills and network through consistent volunteer work in my field so that I can widen my net (although I wonder if volunteer work looks less appealing compared to a candidate with formal paid experience - thoughts?)
-I include the fact that I have a PhD (but not the year) on my resume, whether I'm applying for an entry level or a mid-level role. I wonder if this is hurting me, but leaving it off feels like a lie?

I want to know if I should change my approach or if I'm missing something. Since I started the search, I successfully interviewed and was hired by one company but his new small business ended up failing. I got one take home assignment for another, but didn't advance to the interview stage. I was shortlisted for a third, but that company ended up cancelling the role entirely before further interviews. Otherwise, no bites.

Please stick to concrete suggestions over just validating that it's bad out there right now!