Now, we have ways of earnings for your social activities, please check the post above to see how much you can get for your social activities. There's a lot of difference between those websites you mentioned like adding friends, tagging friends, live chat, etc.
Here are the rates of earnings
1 Point = 1 Satoshi
Minimum withdrawal = 50,000 Points
Not sure how adding friends and tagging friends is something that people would be enticed to, as it's pretty much very similar to Twitter's follow and @tag feature, but the point system is definitely interesting.
Where you are going to get the funds though? Of course for now I assume it's going to come out of your pocket, but what about long term? The points(1point=1sat) looks pretty easy to earn; how would you deal with account spammers? Do you think the potential income from ads and or promotions would be enough to cover the payouts of every single user?
I sincerely wish you the best of luck here.