Despite some disagreement in the thread, one thing is true as you read through: Deadeye is not quite as improved it can be, and even those who have argued against what I propose here in the OP agree, yet with different approaches on the matter. I hope this thread helps Anet's devs want to improve the Deadeye to make the Spec less sluggish and more enjoyable.
Update: The concept of crouch-moving I added to has been added thanks to feedback from casualkenny in the comments below.
After checking out the Deadeye Spec for the first time, I want to give some feedback.
Here is a mock-up image I created to demonstrate what this would look like in-game: https://imgur.com/a/JOaTw76
The concept explained:
When a Deadeye is in ‘Kneel mode’, and then runs either to escape or to reposition at another point, instead of constantly being stuck in one place (unless you keep mashing Skill 5 or dodge-move all over the place [adaptable yet very impractical]), the Deadeye’s skills become temporarily disabled until the player stops in place.
With the above in mind, when a player stops in place, the Deadeye immediately goes into kneeling position, and the Deadeye’s skills are immediately enabled to use. Furthermore, in the event a player wants to move around and shoot things at the same time, only then is when a player is required to manually come out of ‘Kneel mode’ by pressing Skill 5.
Some critics may say the above improvement is OP, yet it is really not, because all skills are disabled while running in ‘Kneel mode’. In other words, this is clearly a fair improvement on a Class/Spec that requires ‘mobility’, and that is what’s wrong with the Deadeye Spec.
What do you think real snipers do? They are not forced to be stuck in one place; they move from one point to another point, and then reposition themselves. Sure, you can dodge-move, yet that is too Kneel, stop, Kneel, stop instead of Kneel, run, Kneel, run (as suggested).
Other critics may say, "Well, I just got so used to using Skill 5." or worse, "Yea, and a single button that does everything for you would be cool, too." and to that I say had the system I propose been implemented in the first place, there would be no going back to the current state of 'Kneel mode'. In this case, it is not about easy-mode; it is about what makes sense when using a firearm in any game, and that includes being able to move freely from one point to another either to escape or to re-position.
GW2 may not be a shooter, but since there is a shooter Class in GW2 that utilizes firearms, what makes playing the Class any different from playing the role of a shooter in shooter games? There is no difference, because let's be honest, you would more than likely throw your shooter games in the garbage if the only way to move from one point to another while using a rifle was to dodge-move all over the place.
TL;DR: Leaving Deadeye’s ‘Kneel mode’ the way it is does not make playing the Spec mobile, realistic, or what have you. The current state of ‘Kneel mode’ is not even a nerf, or a balance, for that matter. It is clunky: instead of Kneel, run, Kneel, run, it is Kneel, stop, Kneel, stop.
The concept of crouch-moving that works on every Class, not just Theif (as initially suggested)
On one hand, I got to thinking the function of crouch-moving (with a new hotkey specifically for 'Crouch-move' in the Settings) should only be a thing on Theif (Deadeye in particular only when moving slow during 'Kneel mode'), but then I got to thinking of the potential benefits of this mechanic and the fun that comes with it, which would also act as a 'ducking' tactic in combat, especially in PvP to lay low and then dodge-roll out from behind walls, bushes, etc.
With that being said in mind, casualkenny came up with this concept, yet it is only linked to Deadeye's 'Kneel mode', so to add to his idea, what I propose to Anet is to have a new hotkey in the Settings specifically for 'Crouch-move', when triggered, has a speed reduction, just like what happens when players have their character 'walk' instead of run. However, the speed of crouch-moving should be a little faster than walking pace.
This would be the ultimate Deadeye experience as if you are truly playing the role of a sniper, and not only that, other classes can have fun with the new 'Crouch-move' function as well.
Thank you for looking into this.