My thoughts in convenient list form (mostly), in case anyone is interested:

• smart scope (zoom/aim down sights):


• I've kind of wanted universal zoom since Halo 1 and more so since Halo 2--
  or, I thought I did...


• I know it affected how the weapons acted, but it was hard to see the difference in non-headshot weapons while playing


• knowing I could always zoom in and have it help me made me feel like I had to always zoom in, like, what's the point otherwise?


• this and having to hold something down to stay zoomed in made it even more annoying than before to get de-scoped by taking damage, much more annoying in fact


• I started enjoying the game a good bit more when I mostly gave up trying to zoom in


• the precision rifles seem like they're still pretty usable without zooming in


• ground pound (can't remember the real name, can't care nearly enough to look it up):


• hardly used it, hardly felt like I had a chance to use it


• feels dumb and kind of overpowered


• they cut crouch jumping for this? ugh


• Spartan charge (press melee while in what I'll call "whoosh sprint"):


• used it slightly more


• satisfying when it works, leaves me feeling like an idiot when it doesn't


• doesn't seem overpowered, somehow


• not partial to it


• auto-stabilize (float in mid-air by pressing zoom or zoom and sprint while in the air):


• felt like BS, although maybe it shouldn't since jetpacks have been in Halo for a while


• I have a hunch this is sort of stealth-overpowered; can't remember my reasoning for that


• got me killed more than once (more than twice, for that matter) because I was trying to quickly take a few shots while jumping and zoomed in


• might be interesting if the game makes use of fall damage


• thrusters (short, quick move forward/back/left/right):


• took a long time to remember to use it-- used it much more on accident trying to zoom in than on purpose


• didn't seem that useful the vast majority of the time


• needs a cooldown meter, more than sprint did in Halo 4 even, especially if I'm going to rely on it


• Spartan abilities in general:


• I tended to not use them much, especially not on purpose, and they mostly felt like a mess, especially all together


• I would be much more partial to them if they were separated out like armor abilities (I'm in favor of the option to have multiple at once via gametypes though)


• sprint:


• it's fun, as always


• having infinite sprint, and having it without a special trait or perk, makes me a little leery, even though it's fun, but...


• shields not recharging while sprinting is an interesting move; I think it balances the mobility, in fact it might be a little bit too much


• slide (sprint then crouch): rarely remembered it, rarely used it; I like it in 2D games and Destiny so I should like it in Halo but I'll reserve judgment until I've actually used it more


• damage and recovery:


• works in a pretty intuitive and enjoyable way


• I like the reintroduction of health, and the introduction of a visual for shield recharge wait time


• the audio on the other hand is bleeping awful, and awfully bleepy


• automatic chatter/callouts:


• the actual lines were very rarely useful


• the lines tended to run over each other


• the female-voiced lines seemed more tolerable, maybe because they were lacking a radio effect


• might be better once I've memorized the callouts, but it's been a good few years and I still don't entirely have the callouts down for Lockout, Guardian, or Powerhouse, so I doubt that will factor in


• I tuned it out most of the time


• overall 0/10 would not listen to again, would cut from final game with ax


• intro and outro:


• the pans across the map in the intro were really nice, and it looks like it might be a customizable thing since it was on Forged maps too, which would be awesome


• your team walking out and standing there in the intro is completely unnecessary but it doesn't hurt aside from wasting a few seconds


• the victory thing at the end seemed fine to me-- until I saw the one you get with teams of three, that seems a lot more braggy and bro-ey than the four-person one, and it bothered me


• weapon spawn announcements and markers:


• I like the idea up to a point


• I think they really overdid it in this


• just showing once where things spawn and maybe one visual and/or audio cue when they're close to spawning would be highly preferable, also floating and spinning is a bit much


• gametypes:


• I didn't play much besides slayer, but breakout and strongholds didn't seem that great-- not bad, probably better than VIP, but not really worth investing time in


• spectator mode:


• pretty slick; I only used it once but I could see myself passing some time with it, waiting to join people or just when I'm really bored


• HUD:


• I still don't like the superfluous lines (protip: I never will)


• I don't care for the text they used but at least it's a little better than the HUD text in Halo 4


• weapons:


• they tended to fade into the background when dropped and sometimes even at their spawn locations, tons of times I had to walk around looking for a hold X prompt to find a weapon I knew was around there somewhere


• the AR, BR, DMR, pistol, and sniper more or less acted like I expected, and they're pretty good weapons still


• the pistol might be too weak, especially considering the precision rifles, but I feel like I'd need more time with it or some hard numbers to be sure


• the light rifle was... odd...


• it kind of felt like what they should've done with it in the first place


• it still feels hard to justify having it and other precision rifles in the sandbox, especially if they bring back the Covenant carbine or the needle rifle


• the three-shot kill might be a bit overpowered, I didn't get a very good feel for the effectiveness of the weapon-- it definitely makes me ask what business the five-shot kill DMR has being in the same game though


• what is going on with that zoomed-in reticle? a line and three triangles? how is that supposed to help me aim, especially compared to the un-zoomed reticle? it could be intentional, which would be a clever way of making it less of a quick, easy kill machine, but it feels like another baffling 343i decision


• the SMG was nice:


• it was more powerful than I expected and more powerful than it seemed at first, but still far from overpowered


• I like the reload animation and the look of it has grown on me


• I think they've found a (second) way to make me actually care about the SMG (the first way was ODST's version)-- they've mostly turned it into a completely different weapon, but for once I think they did a radical change right


• the rocket launcher acted like it did before, pretty much; I was surprised at how little the redesign bothered me in first-person, but there are any number of reasons for that, and I still think it should be black at the very least


• the hydra is a cool concept and I think it has a place in the sandbox but it's too weak to really be useful-- I can only imagine taking on a vehicle with it, you might as well throw rocks; make it a real power weapon and lower the ammo a bit and I could really, really like it


• I couldn't tell the difference in how the regular energy sword and the curvy one acted, if there was one; they both feel pretty good, but I get the complaint about bloom on the curvy sword


• I missed the shotgun, the needler, maybe the laser a little bit, and Covenant weapons in general

Overall, I went in cautious, and my initial impressions were that it was a hot mess on fast-forward, so I didn't play it much. On Friday night though something clicked, and I felt like I was starting to get into it. Probably half my play time was in the last two days of the beta because I wanted to get some more games in to have a solid base for talking about it and because I wanted to pursue this feeling like I was "getting it". I ended up feeling much more positive about the game, because I ended up having much more fun, but this was still by and large in spite of the new and changed things, not because of them.
I'd give the beta a B for effort, a C for execution (maybe C+ if I'm feeling generous), and an A- or B+ for fun level.