So it's not really a buff but more of a modification/balance maybe? Depends on how you view it.
Wraith is a beautiful killer who amazing skins and honestly a pretty decent power. But he's hardly utilized in the high red ranks from what I seen due to the major drawbacks of his power. However the statistics provided by the Devs state that his usage is average. I think a way to increase more diversification of Killers among high ranks by adding Wraith to the fold is to make him completely invisible. Like, Spirit when she's phasing invisible.
Now I say this because Wraith with no add-ons is pretty hard to play. Most of his add-ons to begin with aren't even that great either. If you don't have the silent bell add-on, people will hear you coming a "mile" away and run off before you can do your surprise attack on them effectively. Hell, the time it takes to transition out of the spirit world takes a long time and the survivors already see your movement and have sprinted off, making it hard/impossible to catch depending on the area they're located in. Last thing to add, he gains deviousness points for Stalking, but what's the point of Stalking if a Survivor sees you as you come up so you have to immediately uncloak anyways to chase them? Defeats the purpose of Stalking.
So my suggestion simply put:
1.) Make Wraith completely invisible for anyone to see when he's in the Spirit world. Movements in the grass/corn can still cause sound/movement.
2.) If you want to make Wraith completely invisible, his add-ons NEED to be modified as well. No one wants a Wraith that is standing right behind them and IMMEDIATELY coming out of the Spirit world to hit them just to disappear and do it again when Survivors think they're safe. That's just too OP.
There's probably other adjustments you may or may not need to modify if you do this. Like his speed when he's uncloaking or how fast his movement is while he is in the Spirit world.
Would love opinions or better suggestions. But Wraith needs something, his Skins are too awesome and his play is too great to be a (below) average killer.