Hi.
I suggest you include only ranks starting from full member.
These are the most suitable rates right now.
Full Members: 0.007 BTC
Senior Members: 0.0125 BTC
Hero/Legendary Members: 0.025 BTC
You need to decide how much you plan to pay for your advertising per week and then come up with how many members you're going to include in your campaign.
For example if you plan to pay 0.295
BTC per week, the campaign would have 25 participants (10 full, 12 sr, 3 hero) or any other way that you think suits you.
And according to that decide how long you want to run it. (Don't forget to add the manager's fees).
If you don't have a manager and are still looking for one check this out:
https://bitcointalksearch.org/topic/m.22375093Regards