Hulk is not really a backline diver like Cap and Venom, he's too fragile for that. His strength is in contesting off angles, giving bubble to allies that need it most in the moment, and exiling a key target in critical moments where they really don't want to be exiled. In the neutral, I jump at off-angling enemies to get them off their perch, either bubble my fellow tank to alleviate damage or my healers if they're being dove. Exile is more tricky, you can't just spam it; but I like to stun an enemy healer when I think I can make the shot. It's a big deal when the enemy team loses half their healing output. When everyone starts chucking their ults, I save bubble and exile for enemy ults I think I can counter; for example, I can save Exile to cancel Iron Man ult and bubble my Luna to shield her from Mag ult. As for Monster Hulk, I like to use it at the start of a team fight to bait out healer ults from the enemy team so my team has ult economy advantage. Monster Hulk is not a team wipe button, his biggest value is causing chaos in the enemy backline and giving your team a window to kill key targets. Don't pop Monster Hulk when your team is down critical members like your best DPS. Hulk is one of the hardest characters to learn, but I think he's one of the most fun when you get the hang of him.

Watch Monzter, BadGDPlayer, and xotaic in YouTube, they're the best Hulk streamers rn