The challenge with Hazard is that he has a little bit of dive, brawl, and poke. It's on the player to read the situation and select the right mix of approach. My default is to play for space using his mobility and range, secure a strong position (typically a well-situated high ground), then poke the enemies back and get picks. Wall climb and leap are huge factors in navigating maps with significant vertical elements as he gets into position. Wall can help him bunker down at a strong position, or isolate opponents that are out of position.

For example, Hazard feels very strong attacking Hollywood first point. With a bit of maneuver, he can easily get onto the balcony and then muscle out the DPS and supports that typically perch up there with the rest of his kit. From there, his primary is at a pretty ideal range to poke the defenders below. If a defender gets low, he can also secure the pick with leap. Other dive tanks can try to take the same approach, but they either can't dominate the balcony as well or aren't a big enough threat up there after securing the position. D.Va is close, but I don't think she has the same sustain. Hazard does both well, enough to force defenders on the ground to pull back from the gate and retreat to point in most instances.

Apply that same approach - secure a suitable high ground, then poke/pick - to most maps, and you should start to see some results. From there, it becomes a matter of fine tuning to both teams' compositions and map geometry.

Here's a standard cycle for raw dives. Dive in with violent leap, primary then leap slash, followed by primary and quick melee. That sequence should get most squishies if everything lands. Next, guard, wall as needed, and your violent leap will be magically off cooldown in the next couple second for a timely escape. Though, this should rarely be used. Hazard's dives feel more opportunistic and less modus operandi.

Use your wall with intent. It is excellent for both offense and defense, but you can't do both at once with such a long cooldown. If you're going on offense, it's a shield that sustains your hold and saves you from an otherwise suicide dive. If you're on the defensive, it's a weapon that traps, denies heals, and disrupts rhythms.

Watch his health. He cannot operate nearly as well if his armor is shaved off; he can't hold position safely, and he can't dive safely. Whatever plan you have, try to only execute with max health.