Great that co-nexx.us, Haven and other social media chat apps that will run on cMixx are in development!
However, the last time I checked out the Connexxus website, IIRC I saw “No Ads and Free to use”.
If this means that users can send unlimited messages for free, then the node runners pay the bill AND zero demand for xx coins.
So, better would be, daily 10 or so messages for free and if you need more you can buy credits.
You can buy credits with xx coins, but I think it’s good that you also can pay for the credits by watching an ad over cMixx (private advertisement, like billboards ads along the roadside). The advertiser pays for the credits with xx coins.