As a game, I found it much more satisfying than Destiny. There was a lot of replayability packed in there. It felt like a complete package.

As a story... not so much. I liked the interaction between Chief and Cortana, but not much else.

Regarding the future, 343i seems like they've learned lessons from their game design failures on Halo 4, but I honestly have no idea where the story is going to take off from here. On the one hand, it does seem like they're putting more attention toward things like continuity, and the recent lore Q&A is a great example of what this approach can achieve for the canon. On the other hand, Escalation has only escalated (hah!) in the magnitude of its mediocrity over time. I don't exactly HATE it, but it's a far cry from what 343i could be doing with this universe and these characters.