I find it rather peculiar that you can sort questions by featured. My arguments:

1. What does order mean in this case? It could mean the bounty amount (e.g. using desc would return the questions with the highest bounties first), but it currently doesn't. The lists seem ordered by something else (activity/votes/...?) but I don't know what, I didn't have the time to test that.
2. It would make sense to have a separate call, such as /questions/featured because this way one would be able to sort that list by other parameters (sort by bounty, views, votes, ...).

What's your opinion on this?