Haven has 3 bombsites: A, B, and C. This makes it an attacker side map.
It is important not to over rotate on Haven as enemies will usually lurk up B or quickly rotate from A to C site.
Sova is one of the strongest initiators as his Recon Bolt can cover many important sites and his drone can help clear close angles.
Shotguns can be very strong on Haven as enemies are forced to constantly clear many different close angles before entering a site.
Agents like Jett, Omen, and Chamber should use the multiple boxes and platforms to stand at elevated off angles.
When rotating through B site, make sure you have your crosshair ready to peek mid since enemies will lurk up there.