I think 4new would get a better boost in social media if they rewarded for initial participation as well, as in an airdrop, and then additional reward for referrals
Well, an airdrop would definitely boost the project's publicity. But I still think it also attracts a lot of people who are only out for the money and don't really care about the project and what it is trying to achieve.
Airdrop could be nice option. I don't know the history why 4NEW did not opt for one or have already completed airdrop. But airdrop sometimes also cheaters and scammers into the project and they dump the tokens for quick money. So I would avoid that incase of 4NEW as this is a quality project with mission and vision in mind.
Airdrops are a good and a bad thing. Good in the fact, it gets the project more known within the crypto community, but bad in the fact that usually these "free" tokens / airdrops will just get sold straight away as soon as they are worth any cash.
I think in the long run, it serves well. I've had an airdrop before which made me look the project up and I ended up investing some fiat into the project after I read up on it. depends what way you look at it