First, I'll say that the campaign is probably the highlight so far. The story was interesting, the characters were pretty good for the most part (Lodi surprised me as a not-pathetic male character in this fucking game, but Orin's babbling got on my nerves a little bit, though that got better once her brain was less scrambled), and it left some implications for where things will go next. Bungie did drastically oversell the "non-linear" aspects of the campaign, though. The implication was that you'd be able to do a lot of stuff in any order, but the reality was still a mostly linear main campaign with some optional sidequests you could do whenever, even after the campaign was done. I'll channel Mald and scribble out a rough idea of the actual campaign structure:

TL is Time Latch missions, which are a little shorter than the main missions but basically the same sort of thing. Completing the main strangelet missions unlocks a few sidequests, but you don't have to finish those for the main campaign. In total, when it comes to just the critical path, the only non-linear aspects are choosing which of the two first zones you work through, and which order you do the Time Latch missions in the last zone. Doing sidequests along the way will make things a little less linear, but I don't think people usually count those anyway. There are also some other steps not listed, but they generally involve basic exploration.
Kepler as a destination is...eh. While it's definitely suitably alien, it feels like a few other previous destinations put in a blender, and the pseudo-egregore fungus wasn't an appealing visual for the various areas it was in. I also don't know how or why we have another enclave of humanity that escaped the Collapse, but at least they're actually physically present in the world and not a few holograms in an empty city. Again, the "Metroidvania" aspect was very much oversold, where you weren't using these abilities to find new areas, but instead just going back and doing a short puzzle to open a chest for loot. Or sometimes not even doing a puzzle, literally just opening a chest now that you had the right ability unlocked. The abilities themselves are okay, but the biggest problem most of the time is just finding one of the activation nodes to actually use them. Can't tell you how many times I've had to run around in circles when I
know what I have to do for a puzzle, I just need the damn fungus. Oh yeah, and the Sieve activity is kind of pointless from what I can tell.
That's about all the positives I can give, so straight into the negatives. First off, the grind is
atrocious. Bungie apparently thinks that the solution to flagging player numbers is to implement a ridiculous grind to get better loot, and then not actually make you feel more powerful in the process. After grinding up to 200 power, the only way to continue to progress is to engage with the Portal (and hoo boy that's coming), where you'll get tiny upgrades of a few power levels at a time, and only if you're engaging with content that drops a lot of stuff. You slowly have to work your way up to where you can unlock a new difficulty level, and all the while you're never actually getting any stronger because
every difficulty has a fixed power delta between you and the enemies. So every time you gain a level, so do they. And then that higher difficulty is only harder because enemies are now at an even
higher power delta, which once again can't be outleveled or overcome. And to top it all off, all your progress beyond level 200 will end up resetting in six months because the retarded game director thinks this is Diablo 4 and players will just love having to regrind everything again every time a new expansion comes out.
Tiered loot is another retarded idea that I'm baffled even got past the drawing board. The only reason to engage with higher difficulty content is to acquire higher tiers of loot; weapons have more enhanced perks, while armor comes with higher stats. Trouble is, you need to do a huge amount of grinding just to get to the difficulties where you can get anything higher than T2 gear, so the carrot is so far away that it might as well not exist. On top of that, you're incentivized to use the new stuff because of the boneheaded "New Gear" modifier that automatically gives a damage/health buff to newly released weapons/armor (and a "curated" selection of older exotics, fuck you if you liked any of the other ones)...which of course goes away six months later when another expansion comes out and you're forced to grind the new shit all over again. And, of course, you're
still at the mercy of RNGesus, where it doesn't matter how many perks a weapon might come with, you could
still end up not getting the roll you want even after hundreds of drops.
The stat rework is also bizarre. The old system had some issues, sure, like tying different classes' ability regen to different stats, mobility being effectively useless (which really hurt hunters), and every build pretty much sticking to the same distribution (stack resilience to 100, high discipline/strength stat depending on build, pump the rest into recovery and dump mobility and intellect). The new stats are just weird, though, with the stats not only affecting your baseline regen but also how much you get back from other sources. The goal seems to be forcing you to do more tradeoffs for your stats instead of being able to pump everything you need, but all it does is make you feel weak, especially when all you're getting for new armor is shitty T1 gear with barely any stats. Armor now has archetypes that make it easier to figure out what stats it has (one fixed big spike, one fixed lesser spike, and one random stat), but there are only six combos out of a potential thirty, so some combos like weapons and super are impossible to boost as effectively as you want. Oh yeah, and the weapons stat is stupid, having to spec into a stat to simply make your guns work better. Who the fuck came up with this shit?
And then there's the Portal. Hoo boy, where do I even start? Aside from looking like a shitty mobile game UI, the Portal is just stupidly barebones. You have a small selection of stuff to do, all of it from past expansions, and the best thing to do that day depends on what bonus loot each activity rolls with (and when you use up those bonuses, fuck you, grind the same shit). The "playlist" versions of the Solo/Fireteam Ops are more or less irrelevant since they offer much less loot, so you're better off picking something from the list...except the Fireteam Ops individual listings don't actually have matchmaking, so have fun running those strikes solo (which yeah, it's nice that's an option finally, but could we have the option to matchmake for those?). Bungie also disabled the best farming method in Pinnacle Ops because it was too rewarding, can't have people shortcutting the grind that quickly (never mind it still would have taken dozens of hours to get close to cap)! And with regards to desaturating the old Director, they literally said that their playtesters automatically gravitated towards it because they were familiar with it, so they desaturated it to discourage them from using it, as opposed to, I dunno, taking that as an indication that the Portal sucks?
I haven't set foot in the new raid yet, but from the discourse around it, contest mode sounded brutally overtuned; teams were having to hotswap multiple times
during DPS phases to eke out as much damage as possible and still coming up short. It didn't help that, allegedly, there's a bug where loading into an activity sometimes gives you different damage numbers than you should be doing, so that's fun. I'll probably try out a normal clear later on, but also, laughably, everything's only dropping at T1. Endgame activity, T1 loot. Bravo, Bungo. Supposedly you'll be able to do challenges later to bump up the loot tiers, but honestly, what's the fucking point?
And then there's all the minor miscellaneous stuff that is just baffling and stupid. No new crafted weapons at all is absolutely retarded; I do not know why they have such a hateboner against crafting now, but if they seriously think that taking it away as an option is going to drive engagement numbers, they're in for a rude awakening. Not even implementing it for the previous episodes' weapons when they said they were going to use crafting as a catch-up mechanism for people who weren't around then is incredibly tone-deaf. Tower vendors are basically useless now with the removal of all their rep tracks, although I'm glad I didn't spend any time in Trials last season because now I can just buy all those armor sets for nothing. No new ritual weapon, and ritual playlists are basically dead content (although you can still gild your Dredgen title, which has a hilarious bug where it increases your gilding every time you go to orbit). And then an assortment of miscellaneous bugs that are baffling they even got through QA (oh wait, they fired their QA department).