There is no justification for The Legion's immense power drawbacks.
Feral Frenzy's movement and vaulting speeds are underwhelming and the cooldown stun is long enough for any hit survivor to reach a loop. Additionally, the cripplingly long recharge time makes it impossible to use the power for mobility. Even when you use it perfectly, you need the survivors to be really close together to even injure more than one survivor. The best any realistic Legion player can hope for is one hit and a bit of information.
First of all, I wanna say that I get it. Especially newer survivor players don't understand how unimpactful an easy first hit really is. This means that The Legion being viable would offend a lot of people considering them cheesy and uninteractive. Some killers are just supposed to be weak I suppose.
However, I am just unhappy with the insane drawbacks that there are for just pressing M2 at all. Even when you always use your power perfectly, you end up as a weaker Plague. There is no justification for instantly consuming the entire power bar on a missed hit and hiding Sprint Marks.
As a survivor, you can just let The Legion get their first hit and either use the cooldown time to reach a loop or just instantly start mending as soon as they go for someone else. Removing the mentioned unnecessary and frustrating drawbacks wouldn't even begin to make The Legion threatening at all (which, again, I understand and respect).
So, why not make them a bit less frustrating to play when they're supposed to be weak anyway?