As myself, I am more willing to participate in old tokens or bounty projects that have been trading tokens for more than one year. I missed many airdrops of projects such as XLM, I think there are still some contents that are valuable.
So I think that those who like bounty projects can exchange more together, so as to avoid missing some good content and waste time participating in some garbage projects.
Where do you find the bounty or airdrops for the old projects ? The airdrops / bounty are mostly for the new projects or ICO and we can only guess if the bounty we collected could be valuable in future or not. I myself have collected few ICO coins which had good rating on ICO ranking websites but they failed miserably. Collecting bounty is like a gambling, it may be a hit or just a waste of time.
Therefore the bounty project is difficult to predict even though it looks interesting and a good team and their concept is good if it fails in its sales then the project is nothing and the same is the case with the bounty as well.
I myself have joined many bounties available, but only a few have good potential for the future, so it is indeed difficult to choose bounty.