If you have the time you can do both, but there's no guaranty which between the two can give you the most profit, but I'd like to remind you of the long wait, airdrops, and bounty take two months to a year to see if the project you've worked with has potential, I've participated in so many airdrops and bounty campaign that I've forgotten the name and sometimes I'm just surprised that some coins are coming  without remembering when I promoted it, because I don't keep a list of my campaigns.