The way the cooldowns seem to work is, in Razor Wings’ case, no matter how many or when you spam razor wings, there will be a 10 second cooldown in between each charge. As in, spam 7 wings, take 70 seconds to get them back.
What should be happening, logically, is that each charge has an independent cooldown. Ergo, if I spam 7 razor wings, it should really take about 11 seconds to regain them all, as each wing’s 10 second timer would have all started within the 1 second (or however long casting time is) to spam them.
The way it is now, it’s virtually impossible to create an endgame build around because the only way to get them back quickly would be to use the Ultimate passive free casts, which is fairly unreliable and doesn’t work on bosses, or to get your cooldown reduction way up, but even that has severe limitations.
If the number of Wings is already hard capped at 12, why do they need another huge cooldown?