I'm rather disappointed in myself for picking Overwatch 2 as my most anticipated game of the year because it is, in my not-so-humble opinion, more of a full-price DLC. The new maps, modes and heroes will be playable across both titles, with all of your unlocked customisation options carrying over into the "sequel" should you choose to upgrade.
Overwatch 2 promises to keep things fresh by allowing players to modify their abilities, maybe trading a little bit of burst damage for more consistent DPS, or vice versa. The mission variety is what will make or break it for me. I'm hoping for both short and long missions, some adding to the overall narrative and others just there for intense, horde-like, firefights.
When it comes to PvP, there are significant changes being made. Overwatch will shake things up by transitioning from 6v6 battles to 5v5, with teams losing one of their tanks. This would make some of the "off tanks" a terrible choice in the current live game but, with a host of reworks in the pipeline, and not just for the tank class, I'm hopeful that players won't feel pressured to choose a barrier tank.
In fact, tanks may not be tanks at all; Blizzard have expressed a desire to switch the name of the class to brawler. Still, it's hard to see the benefit of forgoing a reliable Reinhardt in favour of a dive-bombing D.Va. Heroes are already getting slight tweaks and reworks (though, like most multiplayer games, this has been a constant ongoing process throughout Overwatch's life), suggesting that the developers are going to drip feed changes until the sequel's release.
I've read and heard nary a thing about the Overwatch Workshop, a tool for knocking together custom game modes. It's already being used in creative ways and could add endless longevity if it's expanded to allow for the easy creation of new missions, not unlike the track editor in the Trials series. It's not very intuitive, nor expansive, but imagination can push technology beyond its limits.
As Liam mentioned, Microsoft's recent acquisition of Activision Blizzard means that we can expect Overwatch 2 to be playable via Game Pass from day one. This not only saves money, but also saves me from having to persuade/bully my other half into purchasing the sequel. Playing with friends and loved ones is always more fun and I find that those closest to me are less likely to bitch and moan when I spend a little too long trying to sink a basket in the spawn room.