* Is there a sticky explaining the differences of airdrops vs bounties vs signature campaigns?
IMO, airdrops are not really worth it. Even if you get a couple of dollars worth of coins, you have to move them to an exchange, trade them there, and withdraw them from the exchange. Each of these steps costs money, so at the end, you are left with next to nothing.
Signature campaign is a special type of bounty. You can also have content creation bounty, twitter and facebook bounty, and other types. In terms of earnings, signature campaigns are usually among the most lucrative, but that is not a strict rule. You can participate in bounties where content creation bounty could bring you more than signature campaign bounty.
* Do they favor my status (Jr Member I think I am) ... I know that higher statuses earn more at this point
The majority of campaigns favor your status, yes.
* Can you participate in more than one?
Only ONE signature campaign. But you can participate in several bounty campaigns of other types.
* If you post here everyday as a habit, what's the level of extra effort involved in participating in bounties and signature campaigns?
If you are in a signature campaign, the effort has to do with making meaningful and helpful posts for the community. Some campaigns have a minimum character limit per post, others accept posts only in certain boards.
I'm sure you will find your way around the forum once you engage in these campaigns.
Make sure you read the rules of the campaign thoroughly. I can't tell you how many participants fail to even read the campaign's OP before taking part in it.
Good luck.