I don't think the end of Immortal Hulk means the end of Bruce Banner as he is now, hopefully. That Defenders cover that was teased a month or two ago had both Hulk and Red Harpy on it, along with the Masled Rider Ewing has been hyping for awhile. Could be that Immortal Hulk ends with Leader/OBA's plans stopped and history changed for the better, for now, and Ewing carries the Immortal Hulk cast over to Defenders, maybe later pick up a "season 2" of Immortal Hulk if he sees to resume it.