After spending a couple days of 2-3 hours each on reviewing resumes that were "only ok", we started adding additional hoops for getting resumes in, and also tried to put in a gatekeeper to really urge applicants to write cover letters. After that the rate has dropped to bearable, but we still maybe get one out of 10 applications with a cover.
So, if you are applying to a job right now, I'd say that rather than optimizing your process for getting a lot of jobs applied for, spend some more time and apply for jobs that you're well suited for, and then make a cover letter that explains why.
I've been very lucky, I've not had to apply for many jobs. But when I have, I always wrote a specific cover letter AND customized my resume to the job advert.
But, yeah, we're having a hard time finding full-stack people that can hit the ground running with Java and Vue.