Multiple Ways to Acquire Legendaries
Mm, I think the main problem with that is that the process is a timesink intentionally; all of the suggestions you made are really cool, but also much faster ways of doing it, and the point of legendaries seems to be a long-term goal as you play. To the extent you make it short and sweet, you finish a key portion of the end game much sooner and have less incentive to continue playing.
That is not to say I’m very happy with the system they have now – I have anxiety issues about crowds and negative attention in competitive PVP that stops me from taking part in WvW and meant I had to completely abandon even trying to obtain a legendary (which I was otherwise prepared to do all the pre-requisites for), so I greatly disapprove of the fact that they made playing a lot of PVP a mandatory aspect of obtaining a PVE weapon.
But you have to acknowledge the reasons why the process is meant to be time-consuming, since you are talking about one of the cornerstone projects of the end game. That’s my two cents, at least, as a disappointed but understanding fan who can never get one.