I like me some invisibility and for some it's probably big part of their build or survivaliablity. For those who have costumes for characters that stay invisible a lot or do this passively [Invisible Woman, Ktity Pryde] it can be less fun [It's an assumption].
For me Visions invisiblity effect is great. It look's robotic/ holographic and you know that it's invisibility. Do you think other heroes should/ could have their own invisiblity visuals? I would like that at lest for some heroes.
The generic invisiblity comming from artifacts, omegas etc. would be the same as is [to differenciate and for those heroes who don't go invisible on their own.].