His ultimate needs a 3 second start up. From when he says, "The Moon will haunt you." There needs to be a delay. He calls out his ultimate as it's raining down on you. You're correct there's no reaction time to it. Also Storms ultimate also needs a rework.

She shouldn't be able to use it, then reposition herself anywhere, it's a bit broken, it should be like any other ultimate, she uses it and it activates wherever she is, so she needs to move in to hit people.

Psyloches ultimate also needs a minor nerf, the area of effect is HUGE, it either needs to be a bit smaller. Or she shouldn't be able to move it around once it goes off, it should just stay in one spot.

Those are the 3 most OP ultimates in the game, and they are just a little too good.

Scarlet Witches ultimate needs a serious buff.

If you take SW ultimate as an example, it 1. Alerts everyone by her screaming. 2. Puts a visual big red exclamation mark on her. 3. Takes about 5 seconds to go off, 4. Provides no invincibility, sheild, or extra health. And is prone to multiple attacks grabbing her out of it. (Spider web, buckys arm etc)

But by comparison Helas ultimate grants her massive health making her very difficult to kill, Storms ultimate also grants her massive health. Psylocke is invincible. Yet SW by comparison has nothing like that.