Now, melee is very hard to pull off when the other person has actually seen you. You could see them rolling away to safety and have you hatin. The assault goes after this problem because he has a giant jetpack that he can slam down on his enemies when they haven't noticed and proceed to kill them with their said melee weapon. But a banshee doesn't have that option. in a 1 on 1 fight how could a banshee even hope to win? OBVIOUSLY there are many solutions. that's what this is about, point is: how could the banshee counter the dodge rolling (other than sneaking up behind people cause that's hard enough of foot)

1. Let Banshees run really fast.
2. Make them slimmer than SMs and a bit shorter, so they are harder to hit.
3. When doing a melee-attack and an enemy is nearby but still out of melee-range, they do their screaming and the enemy gets stunned.

Give them a better Dodgeroll then no one can stop them.

Well, whats already hinted at is a ability to deflect bullets with your swords.

It's interesting that Banshees were also factually useless in the Tabletop for a long time.
The Problems were no Transport with Assaultramp, and no assault grenades to melee units in cover. And you would get shot down by Overwatch. Generally approaching on foot was a bad Idea.

How did they change it? Banshee mask stops them being shot at with overwatch, and they are acrobatic , so ignore the penaltys for assaulting units in cover. And they can move further when assaulting.

What does that mean for us:
Give them a really quick jump over cover, I would love if they would just ignore it basically automatically. You run over cover without pressing anything, you don't slow down, you can still shoot and melee.

Make them fast maybe even a special movement ability, and give them something to stop incoming fire. Maybe the warshout that dissorients the enemy, or an ability to block bullets.

Yeah, give them a higher move speed and make the mask an AoE of the new interrupt effect with a cool down. That should be enough and, if it isn't, you can shorten the time on their attack animations so they have more control over their movement.

banshee are planned to have a charge like ability that make them "dodge" bullets.

Of course Banshees can work. They, like any class, should always try to surprise or flank their enemy in order to close distance & get first hits in. Ideally teammates are backing them up too to draw attention or punish enemies should they fire. Being a ground based melee they need additional ways to close the gap and/or something that makes them useful to the team & viable to play.

Eldar will be naturally faster compared to other factions as well as being able to traverse obstacles in terrain quicker (ie vaulting over cover or climbing up something). Speed can make quite a difference in shooters.
Players can customize the capabilities of their class with accessories that modify stats like speed & damage mitigation.
Eldar acrobatics can come into play too in being quicker at dodging leading into counter attacking. Maybe even flip over the enemies instead of rolling around them as we've seen.

In addition to the above, Howling Banshees will be able to deflect enemy dakka using their weapons + they will have a leap. Sorta being a hybrid of the LSM Assault with a jump pack + LSM Assault with a shield, just not able to cover as much distance or block killy stuff as effectively... Please don't try to deflect a missile or lascannon shot. They can't do it forever & it's likely that more shooters = less time or some damage gets through their defense.
I figure a good start for leap distance & height would be Warframe's front flip move. Might even need to be sprinting in order to do it. Unless they want to try treating it similar to Predator's jump in AvP 3 game (can see it in parts of this video starting here @2:33).

"-snip- Howling Banshees fill out the diversity of the ground-based melee character. Howling Banshees perform a function similar to a character with a shield, in that they can charge forward in the open while deflecting small-arms fire (well, small for 40k) -snip-"

- said in Official Basic Class List page 29 post #285 by BrentEllison (Lead Designer and Protector). ​

Then when asked by a crusader how they do that he answers: "With their weapons of course!" - here.​

6. Will assault oriented classes get a leap or charge ability if they do not have a jump pack?

BRENT: It depends on the class. Howling Banshees will have something like that, but for example Space Marine Assaults can choose to take a Storm Shield to make up for the reduced mobility, Chaos have different powers depending on their marks, etc. There’s no one-size-fits-all solution.

- said here in forum Q&A Answers Compilation Thread​

Then there's their scream that hasn't had anything official talked about yet but I figure it can cause suppression, stagger/light stun and/or damage if the target is close enough. It could also impair hearing which would be useful considering sounds are important in a shooter.

Weapon options include spears and hopefully the triskele, these give reach. Spear use is pretty straightforward. I figure the triskele hits harder than a pistol (depending on target & where it hits) but deals damage at a slower rate because it's thrown then needs to return. Maybe it can cause bleed DoT or have a side-grade that does with a trade-off.

Finally throw in the other Eldar classes to synergize with the Banshees such as Warlocks, the Eldar's aggressive support class. [Jolly Cooperation Intensifies]

hmm ... chain sword apoths seem to work, sword weilding aspiring sorcs seem to work

why wouldnt Banshees work?

Make the melee attack of Banshee very fast and high damage and you wont want to meet them in close range.

Because a banshee doesn't have a heal or support that they can sit back in your friendly lines and kill charging assaults. They are meant to do more like an assault.

But anyway, I think for the scream should be quite a bit of range (obviously not that huge but still) and it shouldn't stun because that SCREAMS op (haha get it?) But it should just give a suppression in witch you would have a hard time shooting them because half your bullets are going over to that flaming barrel