I really enjoyed the first five-ten hours but was pretty disappointed after that. Once you've screwed around in the open world for a few hours, the game really doesn't throw many new ideas at you. The last like 5 missions that are all linear were really boring and too many of the boss fights were bullet sponges.
It felt like if they came up with one or two more grapple-hook level tools, then polished a few more things, didn't repeat the same three environments the whole game, it would have been something really special. As it stands, it really falls short of what I thought it was trying to be. It's hard to finish the game and not feel like they were just trying to reach a minimal viable product.
The gameplay is superb, if it's not the best it's just behind Halo 1. Grapple and thrusters are really strong even before upgrading, throwing coils is a solid plus as well. The ai actually attempts to return to what halo 1 tried where they are believable, fun to fight, and imperfect enough. The sandbox might be the best it's ever been even though it's not saying much. The interior sections are really good throwbacks to Halo 1 and run perfectly. The open world is somewhat empty but still enjoyable because the core gameplay loop is great.
I don't think Halo needs bosses but none of the ones in Infinite are as bad as the bungie ones. Only a few were actually difficult.
I didn't play Halo 5 so I didn't really care that they swept in under the rug. I overall liked the plot where it's relatively simpler than the trilogy, although I think they shouldn't have revealed the Harbinger in the trailers. I will admit that I find it kind of hard to view anything other than the Flood as a major threat in Halo now, it seems like the only thing that could be more dangerous than them would be an actual Precursor. Sometimes it felt like the characters gave exposition dumps and some of the bosses taunted too much. I like how they gave Chief some character in 4 and I liked it even more in Infinite. Definitely looking forward to whatever expansions come.