In effect, you'll need to earn at least 1 merit for every 10 posts you write (on average) if you wish to prevent your account from slowly drifting toward a lower rank. And you'll need to get beyond a 0.1 merit-to-post ratio if you're aiming to increase your rank.
How is it going to be. Did you mean after every 10 posts someone make without having one merit, 1 merit will be deducted? Or the merit will not be deducted but the deranking will be based on carry? I think you meant the later. I still like how the merit system is and I will not like anything to be added.
Did you think some people will rank up and later become spammers or you think some accounts are waking up recently which belongs to spammers?
I noticed some people will have 10 posts and not yet have merit consistently, while sometimes they will earn merit.