The Sundial
Season of Dawn introduced the Sundial which, while it was a big step up from the Vex Offensive, was just okay. It was more fun than Vex Offensive but less fun than The Menagerie (which isn’t going away).
The three non-boss room activities were made at least somewhat challenging with the presence of champion-class enemies in tight quarters, and they were far more varied than what Vex Offensive brought to the table.
It was pretty much the same deal with the bosses. The three Psions each had their own unique elemental flair, although more could have been done. For example, what if when you got detained by the void flayer only a teammate could let you out? The arc blasts could have created chain lightning that you had to avoid. Things like that, at least in legendary, would have made things more interesting.
The final boss, Inotam, at the very least was different than the other three bosses if not really much more challenging or epic. This fact does help it clear the very low and disappointing bar set by The Undying Mind in Season of the Undying which was one of the most disappointing moments in Year 3 so far.
Overall though, like I alluded to at the start of this section, The Sundial was just fine but definitely not memorable or anything that should cause anyone some FOMO especially considering you have the best version of this raid-like experience, The Menagerie, sticking around.