We may have confirmation that Johnny Blaze is a part of the MCU (assuming that Marvel TV is a part of the MCU is as well).
It's a poster of Quentin Carnival, which is the carnival that Johnny Blaze was featured in the comics as the motorcycle stunt driver and Ghost Rider.
Now of course this could be just a nod to Johnny Blaze, but interestingly enough, the Blaze version of Ghost Rider did confront the Robbie Reyes car version of Ghost Rider in the comics, as it's said/speculated/thought Robbie Reyes is not a true Spirit of Vengeance.
Next week sees Agents of SHIELD explore Robbie Reyes' Ghost Rider origin, which so far seems to be pretty close to the comics. Maybe (cross your fingers) we'll get a Johnny Blaze appearance on Agents of SHIELD later this year. It would be a hoot if Nicholas Cage returned in the role.