But there has not been a reduction in the number of ad views or ad clicks to support the premise that the ads are not being seen by the ham radio community.
I disagree. You have to look at the big picture from a long range view. I have seen a steady decline in both views and clicks at one of the other sites over the course of a decade. And it isn't due to a lack of traffic. On top of that, before ad blocking add-ons came along, many of us trained ourselves to ignore ads. It almost became instinctive.
A couple of general responses I can give publicly; and the rest we could go private e-mail.
You could offer packages; 30 days, 90 days, 6 months and a year....with quantity discounts. Also, quantity discounts for those running multiple ads.
Of course, you don't want to make it so complicated that it deters from your other Eham duties.
No frills, I would say. 25 words words max....but charged the same if you use 25 words or if you don't use all 25 words. Six classifieds adds max. No bold print. No italics. Links OK.