You're playing him wrong, he doesn't play like other characters. The vortex is the only thing that is keeping him viable at this point, you need to have that down perfect. Next, his strings are all negative, so be cautious when you throw them out. Shit everything is negative now Stick to jump ins and use the strings on punish to get into the vortex. Once you do, don't mess it up and you should be fine.
He's hard as play as now, well, not HARD but he definitely requires as much thought as some of the other mid tiers now, and yes, I believe he is mid tier, everything he has is punishable and his damage is extremely low but I believe his unpredictabiliy with his teleport and hellfire keeps him from being in the low tier. Before the patch (Online atleast) it was just mb teleports for days, braindead. I actually kind of like his nerfs. It means I get almost no complaints for using him, and challenging matches (because everything I do is punishable) are always fun. The main problem is his absurdly low damage, he was already one of the lowest damaging and yet along with teleport nerfs NRS thought it would be a good idea to nerf his damage, which was stupid in my opinion. He's all risk and little reward now, but I still believe he can be effective when played smart. His unpredictability is his biggest advantage, just make sure and stay unpredictable, because once they start to read you correctly, having an extremely punishing moveset becomes painfully evident.