I think it's pretty clear now that Anet can't balance longbow with its current skillset. I think core of the problem is that the weapon is in some way "too easy".
When longbow is properly balanced(damage wise) it's very easy to play and easily beats novice or casual players with its #2 skill. Because of this, it's a popular choice for not experienced players which often can't use #4 skill properly(and make some people nervous about it).
So even when longbow is balanced(damage wise) it often feels like an unbalanced weapon for many players, because suddenly a lot of mediocre players play on higher level than usually.
Longbow never was a good weapon in raids and fractals. Longbow wasn't in PvP meta builds. The only high level play where it was used was WvW roaming(and even then some people can argue that roaming isn't high level play) so I don't think that calling this weapon OP is reasonable.
Currently this weapon in my opinion is not really useful in most of game modes and when it gets to be good(not even meta) it needs a nerf because players complain that #2 is too easy to use while having too big impact on the game. And they are right because there isn't really much of a learning curve with longbow skillset.
I don't have specific ideas how the skills should be reworked but I think some discussion about this could be useful for devs.