Here are some things I'd LOVE to see on a job posting, but never have:
1. Interview process MAX 1 afternoon. We commit to AFFIRMATIVELY giving you an accept or reject within 2 weeks.
(in other words, we respect your time)
2. Need to hire for this position by [DATE].
(this is a real job opportunity and we are not just fishing)
3. We're not going to ask you to spend a weekend on a work sample or to write code for us for free.
(again, we respect your time, and potentially your IP agreement with your current employer)
4. To apply, just upload your resume or send us your LinkedIn URL. You don't have to fill out a 500-form field online application.
(see a pattern here?)
5. We offer detailed feedback after unsuccessful interviews.
(we earnestly want you to re-apply later if you're better then)
6. If you're good but not an exact fit, we may suggest to you an alternate role rather than just reject and make you wonder if you should re-apply.
(serious about finding talent rather than filling a specific narrow role)
I'd also love to see the company publish their current employee retention rate for similar roles, but I know that's asking for a lot.
When I already have a job, one of the main reasons I don't apply to other jobs more often, even ones that look very interesting, is that most hiring processes are opaque, endless, and generally painful. If you're not getting enough candidates into the funnel, maybe include something about how painless your particular funnel is.