ToME: the Tales of Maj'Eyal

I had one playthrough where as soon as I got invisibility things got way too easy (I had the prodigy that reduced your damage penalty). Of course I was still vulnerable to area attacks, but as a whole I regretted taking it.

Is Shadow Veil similar? On the surface, it looks very strong. I mean being invulnerable to status effects is insane.

No, its side-effect is too huge.
Not being able to control your character is very fatal.
It's a roguelike game, you know, people die if they are killed.
And you definitely don't want to hand your character's life to a Russian roulette.