Currently I benefited from the first three you mentioned but never yet on the services. Im really look up to those who are having their services here like signature codes, logo, design, ann thread creation, even art services and many more.
Bounty campaign is not worth it, only wasting your time with worthless coins, avoid it.
Isnt signature campaign considered as type of bounty campaign? No offense, I beg to disagree with you. Im doing campaign too, but I assure you Im not wasting anytime, maybe its true for some projects. But it depends on the project you pick and searched. I can say that because I did earned from it in the past and even now.
Having skill is one factor and a solid asset of a user but and I think using that could benefited us on some campaign that are worth too. Anyway, just my opinion.