If posts have high visibility, I could see this being an extension to signature advertising. It makes sense if you think about it. People sell their personal signatures here all the time. FP even does the signature advertising service.
I’d be hesitant to stonewall a signature for a free service so believe this type of paid service would be better suited to corporate or commercial purposes.
I think it could be beneficial if the person is a prominent member on the site. Not necessarily staff, but someone that is active, posts relatively frequently, and is well known among the members. I've never paid for signature advertising, but I've put my own sites in my signatures on sites when I ran my own. When I was an active member on places, I felt like it helped (probably would've been more beneficial if I was a decent forum owner lol). At the very least, it's getting the word out about your site, which I think is always good.
I’d say it could be a good monetization tactic if you don’t allow users to have signature space in the first place.
However, would users pay for signature slots? It all depends on the monthly costs and if it would be beneficial for them in the long run.
Locking down key features and monetizing them is something that forums shouldn’t do, but it could work if you’d like to turn your forum into a profitable one.
