Melee Balance Changes; past, present, and future.

I want this to be a discussion on melee, what balance changes need to be made to make it viable, and where it failed/succeeded in the past to bring it in line with the classes' other weapons.

I must admit– I have a bias, specifically for Sword, as someone who simply finds it to be the most fun playstyle available. I'll try not to let it leak into my responses, even as much as I know it has into how I've phrased the questions.

I eventually plan to make a video focusing on the timeline of buffs/nerfs since launch to clarify things for the community, partially for my own benefit as someone who has only played since September.

So, here's some questions, especially for our vets who got to see the before and after results firsthand;

1. Which (of the Light, Medium, and Heavy Melee Weapons) do you think are viable on a competitive level? Explain what advantages and disadvantages support your opinion.
2. What specific balance changes do you think went too far, and how would you change the way they went about resolving the perceived problem?
3. Contrastingly, where do you think Melee Weapons deserved the nerfs they received?
4. What balance changes to other gadgets, specializations, and weapons could be considered to improve melee's viability, or prevent it from being overtuned following other changes?
5. If Melee Weapons received a broad buff (i.e. improved movement speed, ability to kick off walls with quick melee, improved lunge, etc.) what form would you want it to take?
6. If Melee Weapons, individually, received specific buffs to give them viability– niche or otherwise– what buffs would you want, and what form would these take? (i.e. stat change, passive bonus, new ability, change in mechanics, etc.)